Which Optional Rules from the DMG Do You Use

[Blue]

I've seen it most in those who last DM'd 3.x or 4e and are now DMing 5e for the first time.

But my experience is in line with yours - granting advantage that easily does not fit well into 5e, and makes some things too easy, some threats too hard, and devalues the few places where certain classes can pay a cost / have a limited ability to grant advantage.

 

[Hussar]

Whee, I'm not the only one to use the morale rules. Yay!

 

[Nikosandros]

I've tinkered with rest duration, but I don't follow exactly the variants in the DMG. I've left long rests alone; short rests are 5 minutes long, but you can't take more than 1 every hour and no more than 3 per day.

I also don't track XP.

 

[GlassJaw]

I really like the Cleave optional rule. It is certainly a boost for the players but I'm ok with that. Melees need a boost anyway. This one is subtle and not something that kicks in all the time and when it does, I haven't found it to be game-changing. Players really like it and I'm all for anything that speeds up combat, even a little bit. Also means I can throw more mooks at the players!

After playing with it for a while, I have considered changing the effect to an adjacent target rather than "another creature within reach" just to bring it down to earth a bit.

I've also used Hero Points. I like them a lot but definitely handle with care! With bounded accuracy and inspiration, they can skew a battle quickly. In a gritty or low-magic campaign, I would use them in a heartbeat though.