There are already weapons with the reach property in D&D5e, like lances and polearms. Shorter weapons do not get a penalty, but reach weapons get a bonus reach and can strike you from afar (like some attacks of huge creatures from example). Lances get a disadvantage to use them to strike creatures at 5ft, but I think it´s the only one. You also have weapons that you can use two or one-handed, and weapons that give penalties when you wield two weapons.
I prefer it that way, do not get penalties to shorter weapons but to give advantages to the weapons that have reach. Maybe it is not as realistic, but it is less messy and in the end, you have the same bonuses/penalties.
The reach system I described uses a single, easily understandable rule that both makes sense and is consistent with how weapons work in RL.
You described 3 different rules and special case scenarios. How is that less messy?
It also would be interesting if they do something different with the armours, especially the medium ones. Most armour is the same, even tho a plate armour or chainmail or scale have very different properties. I do not think they will diverge much on the core rules of D&D5e, but it would be nice if they allow modding support in the game so we can do that.
Back in the day I actually modded BG2 to alter how armor worked, by adding resistances/absorbtion. It was a very different experience, and at least for me far better. There was a big difference in how light and heavy armors felt and operated.
As it stands a high dexterity bonus from light armor and high AC from heavy armor amount to the same thing in the end - avoid getting hit. And yes, I know it's supposed to represent armor defleecting the hit, but you are never hit to begin with. Visually and mechanically it was unsatisfying.
One has to remember that much of D&D mechanics are so simple because players were the one doing all of the maths. To keep the game moving, it had to be as simple as possible. But in a CRPG, it's the PC that does the heavy lifting, and todays PC's have CPU to spare. You can go wild.
Ultimatively, when you're moving from one medium to another, the limitations of the origin medium may not apply anymore. No need to be constrained by them.
