First, I like D&D fifth edition (5e). Well, I like a big part of it. What 5e lacks, IMO, is simplicity. That is why my games (Dark Fantasy Basic and other "homebrews") are often a blend of 5e and Moldvay's Basic.
I also like minimalist games such as The Black Hack and Knave. I do think, however, they have too little stuff, and are not sufficiently compatible to either 5e or Moldvay's Basic for me to use.
So, what I need is a simple system that is somewhere between these games and 5e. A Fifth Edition Hack of sorts. There is already at least one game of this sort - Into the Unknown. And it looks great.
These are ALL great games, BTW.
Here is how I'd make my own.
|Could THIS be a good idea?|
First, we cut ALL the small stuff. A Fighting style that gives you +1/+2 damage, or +1 to AC? Gone. Skill are mostly gone. Class features are 80% gone. Armor and weapon proficiency are gone. Hit points are not defined by class (but Constitution will have a similar effect). "Save DCs" are replaced by opposed rolls. Anyway, we're ditching a lot of stuff to make the game a lot simpler simpler.
Ability scores and modifiers
Probably start with 3d6 in order (or something slightly better) and use a method similar to Knave or Shadow of the Demon Lord:
I am of two minds here....
1) Use "roll under" skills, like TBH; it is what Moldvay's Basic suggests as an optional rule. So, you have Strength 10, roll 1d20 under 10 to succeed. Difficult rolls can impose a penalty (up to -20), but they'll be rare enough.
2) Just add your modifier and roll against a DC form 10 to 30, like 5e. This way, we keep the game "unified", with a single mechanics, and we can use the 5e DCs as written. Hum... Probably a good idea.
Proficiency is a bit harder. the 5e method is simple and works well. However, I like the simplicity of TBH. I dunno; I think I'd rather assume proficiency since most rolls will be made with proficiency anyway.
Maybe the Thief gets some skills (i.e., some bonus), and that's it.
Another options is defining skills by ability and class. This one is pretty obvious (and is described on the 5e DMG): thieves are "trained" in Dexterity and therefore Acrobatics, Sleight of Hand, and Stealth, and so on. Works well enough, but there are a few exceptions. IMO, the cleric should get religion, the fighter, animal handling and survival*, and the thief, perception. Charisma skills (deception, intimidation, performance, persuasion) are all over.
* This works for rangers, barbarians, hedge knights, mounted mercenaries, and even noble knights - they are supposed to be able to hunt, etc. There is a "rural"/"wild" feel to the fighter, as opposed to the "urban" thief.
Again, "roll under" would be good. The problem is that someone with Dex 10 will make a save against an ancient red dragon 50% of the time. TBH has a good solution for this (HD), but doesn't wok perfectly with 5e, since HD is less important than CR in 5e.
So, this is an opposed roll; one side rolls, adds modifier, and tries to beat the other.
Forget proficiency in saving throws, since we're not using that anyway. The Fighter is better at Strength saves by having great Strength, and that's it.
Maybe monsters still get their usual saves, since we don't want to rewrite their stats.
This is harder. Well, attacking is an opposed roll against AC.
AC is calculated more or less like normal, but AC will be a little higher than usual - because modifiers are bigger and other things.
Damage is 1dx+modifier. Notice that this modifier will also be bigger than usual.
HP - keep them as written for now.
Here is the fun part. Every class has exactly FOUR special features.
You get one feature PER TIER; this means, levels 1, 5, 11 and 17. These are the official "tiers" of 5e.
Level 1 features are things that define your class.
At level 5, you get a second attack (fighter), double the damage of your spells (wizard), get a small bonus to all skills plus more damage to your sneak attack (rogue), etc. And again for levels 11 and 17.
Leveling and feats
Every level, you can make a choice - raise one attribute (probably limited by tier) or get a feat.
My favorite method: spells are feats, and they are flexible. A "control fire" spell allows you to fireball, protect against fire, light a candle, etc. However, maintaining compatibility would also be important, so we could keep it traditional and leave this is an alternative.