D&D 5E Heavy Armor Master VS higher Constitution

[ECMO3]

It is never really trash, though. High level melee PCs with heavy armor tend to get hit a lot. You reduce a smaller percentage of each hit with the feat, but you also tend to take more hits overall to offset as you advance. In some games, especially those in which DMs prefer to use a lot of low level monsters, it can be very effective all the way up to 20th level.

However, I would not take a Strength ASI in 5E. There are a lot of Strength items in 5E that exceed the bounds of what you can get by raising the strength of a PC through ASIs. They also tend to be favored by DMs as treasure as a selected choice. More often than not there is a Belt of Giant Strength in the party by level 10. As there are so many good melee feats out there, I would not take the strength increase when it might be negated by a magic item soon. This is, howeverm something that I might not say if the DM were to allow the player to reverse an ASI and take a feat instead.

Strength items are common, but usually it is the lower strength characters that benefit the most from them and most (all?) of them are attunement as well. This character already has a 17 strength, it will be an 18 with HAM, so he probably won't be taking a strength-based item even if we find one.

 

[MostlyHarmless42]

So personally I'd honestly suggest a different route that is less optimized: Take shadow touched as early as possible because honestly out of all of those build options the only thing that is even remotely "Raven Queen" themed is that feat. Your table may vary, but for many tables level 11 is a LONG way away in most games and by the time many players hit there the campaign could very well be wrapping up. If you think the whole Raven Queen angle is a core character thing (and not just something tacked on) you'd be best off getting that feat asap, whether it delays your strength/con progression or not. Frankly one does not need 20 strength until after level 12 anyway, and I'd personally suggest taking any once you hit 18 strength BEFORE getting it to 20. But that's my opinion and won't be universal to everyone.

One other note to consider though: Is your character the group's "tank"? If so I'd suggest you actually do anything you can to have a 14 starting Con minimum, even if it means making Strength 16 or 17 to start. 14 Con is the MINIMUM I'd suggest for any melee and frankly you're going to be far less durable any anyone who has a higher con (especially if you're not using a shield). This is even more important if you are the only melee in the group.

That aside...
With a choice between Heavy Armor Master or just more con it's really up to you. Heavy Armor master as a feat is more than serviceable. As some have pointed out, yes, it doesn't scale up with monster damage all that great, but I'd hardly write it off entirely. The vast majority of monsters in 5e don't have magical attacks, so it will still do something even at higher levels. 3 damage reduction may not seem like a lot, but it every little bit here or there shouldn't be underestimated, especially if your DM is regularly throwing monsters at you in large groups or ones that have multiple attacks (remember it's 3 off of every attack). Conversely if you're expecting to be fighting a lot of spellcasters and creatures that deal elemental damage? In that case Heavy Armor Master is a bit less useful.

Like any good feat option it's entirely situational and there is no "better" option, merely different pros and cons. Thankfully this is a good thing. Just weigh the pros and cons and do what seems best for your character, not the optimization.

 

[ECMO3]

So personally I'd honestly suggest a different route that is less optimized: Take shadow touched as early as possible because honestly out of all of those build options the only thing that is even remotely "Raven Queen" themed is that feat. Your table may vary, but for many tables level 11 is a LONG way away in most games and by the time many players hit there the campaign could very well be wrapping up. If you think the whole Raven Queen angle is a core character thing (and not just something tacked on) you'd be best off getting that feat asap, whether it delays your strength/con progression or not. Frankly one does not need 20 strength until after level 12 anyway, and I'd personally suggest taking any once you hit 18 strength BEFORE getting it to 20. But that's my opinion and won't be universal to everyone.

The campaign is against Vecna. There is a very strong tie to the Raven Queen. Shadow touched is thematic I agree, but the entire character build, backstory and in fact the plot hook itself is closely tied to the RQ.

Also just being a Shaddar Kai alone ties one to the Raven Queen as S-K souls all go to her to be reincarnated when they die (at least in some versions of the lore).

The campaign goes to level 20 and I am confident we will see it to the end as we have went to high levels with this group before.

The first two fighter subclass abilities favor a high strength. Instill Fear, the 3rd level ability, keys off the amount of damage you do in a turn, which is higher with a higher strength and the 7th level ability - Intimidation Tactics - keys of a contested intimidate check with a bonus based on your strength and a graduated success (the higher you succeed by the better the effect). So there are subclass reasons to max strength quickly.

I think I will go 8 levels to fighter though to get that 3rd feat instead of waiting to 11.

One other note to consider though: Is your character the group's "tank"? If so I'd suggest you actually do anything you can to have a 14 starting Con minimum, even if it means making Strength 16 or 17 to start. 14 Con is the MINIMUM I'd suggest for any melee and frankly you're going to be far less durable any anyone who has a higher con (especially if you're not using a shield). This is even more important if you are the only melee in the group.

There are 4 people in the group and 3 of them are melee oriented.

It depends on what you roll obviously, but 12 is generally the constitution I target for tank characters unless I am playing a Rune Knight. Usually scores higher than that are going to the main abilities for the classes, multiclass requirements or skills I am going to be proficient in. Usually I don't like to use it as a dump stat and go below 12 but 12 is usually is enough and I want the points elsewhere for various reasons. I have played tanks with a 10 con successfully into tier 3, that is difficult but still doable.

However, I also almost always get the shield spell and absorb elements. So I am usually running an effective AC in mid 20s or so and a 12 CON with primarily d10 hit dice is with a very high AC is better than an 20 CON and a low AC. I think this will only be the second melee-oriented character I have played that does not have the shield spell and the other character without shield did have a 16 Con at level 1. The main reason I am thinking about 14 con here is my AC will only be mediocre; 17 to start with chainmail and top out at 19-21 in plate (not counting magic items) depending on whether or not I am using a shield.

I think consensus based on the discussion here is the Heavy Armor master feat will make me more durable than a 14 constitution at lower levels making it a better choice. Late it probably won't keep up, but as someone mentioned there are feats that can tack on a boatload of hps late game, where it is more costly to do that now.

I also can get resistance to all damage multiple times a day through blessing of the Raven Queen and the number of uses scales with PB. So tier 3 that is like 4 turns a day with full damage resistance.