But somebody needs to, and I, for one, would be happy to hear their thoughts on how they think people should accomplish this for a change.
It depends on the changes you (and your group hopefully) want to achieve.
A few examples:
Attack rolls are too successful
My table hates how easy you hit in 5E. Successful attack rates are roughly 65% +/- 5%. Way too high! The sweet spot is close to about half that for us, about 35-40% roughly. We tried various ways to achieve this, and ultimately decided on disadvantage, meaning you roll two d20s and use the lower roll. You don't
actually have disadvantage, but the mechanic is identical.
And, happily, it works great!
Hit Point bloat is out of control
Hand-in-hand with the prior issue is too many hit points for creatures and PCs alike. An orc with 15 hp? Seriously? It should be reasonable feasible to one-hit an orc, but in 5E it really isn't. So, again, we tried various means (half listed hp was the first idea) but ultimately decided to remove CON bonus from hp. Why? Because hp are abstract and not just meat points, so why should bonus hp come just from CON? Makes no sense really in that framework. For example, an ogre RAW has 59 (7d10+21) hp instead has base 38 hp (removing the 21). Finally, due to hp being abstract, you add the
highest ability modifier (maybe CON but doubtful). In the case of an ogre, the STR +4 would give you 42 hp.
This works out to most creatures averaging about 65-75% of their listed HP.
And, again, it works great!
Spamming Attack Cantrips is Annoying
Oh, the
pew pew pew of casters using cantrips in combat---how dull, boring, and not really "magical". So, we made cantrips recharge on a 5-6 instead of usable each round. Sure, making them actually use a weapon in a fight might not appeal to you, but we like it more.
Cyclical Initiative is Boring
And so cinematic initiative was born! On your turn you do one thing and then it moves on until you can act again. Once all your actions are done, the round is over (short version).
And so much more... To date, our "mod" is about 60 pages (reduced from a peak of 150 to bring it closer to RAW).
We also removed Barbarians, Sorcerers, and Warlocks at one point, later restored Barbarians, folded Sorcerers into Wizards, made Warlocks half casters, and so on and so on and so on.
So, yes it's a process, and depends on what you want a chance to accomplish.