Here's how I think they should do feats:
* Characters get a +1 ability score increase at every 4 character levels (4, 8, 12, etc).
* Characters get a feat at 1st level, 3rd level and every 3 character levels thereafter, like 3e (1, 3, 6, 9, etc).
* A character can exhange a feat for a +1 ability score increase.
Breaking it down this way accomplishes several things:
1* People aren't "punished" for taking feats. They still get precious ability score increases.
2* By having smaller feats, players have a much greater ability to customize their characters compared to the bulk package feats they're using now.
3* Feats are still entirely optional. People who hate feats can still trade them for ability score increases; feats are just worth 1 ability point instead of 2.
*4 A character who trades every feat for an ability increase would have +12 total ability points by level 20. That sounds like alot, but that's only a couple more than what most classes in the last playtest packet get. That's a +6 difference in ability modifiers (which is what actually matters) for the cost of taking no feats whatsoever. I think that's fair and not at all game breaking, especially with the ability score cap of 20.
Feats are a more complicated matter than it may seem.
You are suggesting to have feats and ability score increases to be like in 3e, with the additional option of giving up feats for more ability scores (but not viceversa).
I liked how feats worked in 3e, thus I would have no problem with going back to the same system (which was also the case in 5e until summer 2013).
For the general idea of allowing swapping between a feat and a + to ability scores (whether it's one-way like you suggest, or two-ways like the current 5e rules), all that really matters is that in general the two choices are balanced with each other. Obviously for a specific PC there is always going to be more and less convenient choices, but
in general terms feats should really be made worth as much the ability score increase. IIRC the current 5e rules grant 2 ability points, thus feats should be designed to be that worth, while in your suggestion they should be worth 1 ability point. Because of this, I think your remark 1* is a bit off: if you feel that people are "punished" when taking feats, to me it simply means feats should just become bigger.
Then
size (of both feats and ability increases together, once it's clear that they have to "match") is a design choice. I agree with your point 2*, the current design choice of "big feats" has removed (or decreased) the option of one playstyle element, that of fine-tuning PCs, from the game. This is some sort of flaw, because if feats were small (to the point that each feat always carries ONE benefit only) then the game would be more inclusive. If designers want to preserve the option of feat vs ab.increase swapping (which IMO is a good thing because that too makes the game more inclusive, since nobody HAS to take feats, and nobody HAS to take ability increases), they could still pull this off by using smaller feats that are equivalent to a +1, and then just give them out more often if needed.
Sadly, the real reason for the current choice is really that there are gamers who hate not getting all benefits immediately when increasing even-valued scores, and thus complain about getting +1 only (although IIRC there weren't many complaints during 3e...).
Still, balancing feats against a +1 ability increase instead of a +2 would have plenty of good design benefits:
- it would re-introduce the fine-tuning playstyle for those who want (while those who don't want, will choose ab.increases)
- it would encourage increasing other ability scores instead of your highest one when this is an even number
- it would make a feat (or ab.score increase) more balanced with class/subclass features gained at other levels (currently, IMO they are not... the "feat bump" is typically bigger)
- it would avoid overlapping of feats benefit (e.g. there will be several feats granting you the same proficiency in order to make the real benefit work as intended, but then if you want two archery feats you'll get bow proficiency twice OR you might already have it even when taking the 1st feat; smaller feats as in 3e would have allowed proficiency to be a feat of its own, thus avoiding overlapping i.e. "wasting" part of a feat)
- it would immediately increase the number of feats available, just because we could split e.g. 10 big feats into 20 small feats
[The last point is complicated for me to explain why it makes a difference... let's just say that when I read the current list of feats, almost all of them either make you an expert at a certain combat style or carve a special niche for you, such as dabbling in spells. Either way, they
strongly characterize your PC. When writing my playtest feedback (which included the question "are there enough feats for class X", for each class) I realized that except for the Fighter who obviously is naturally drawn towards more combat capabilities, I just had no idea of which feats I could choose for anybody else, unless I wanted it to be a specialist in a fighting style or an oddball. Number of feats available would likely make it easier, but also by splitting them up the choice wouldn't be that dramatic... I wouldn't have to choose to be an bit archery expert or a big 2WF expert, so the choice would also be more relaxed since I'm not so concerned about regretting it later]
But anyway the previous points are more than enough for me to
largely overtake the problem of even-numbered ability scores! And it does bother me to realize that is the sole reason that spawned the mega-feats design decision.