Rolls

Problem: there are 3 types of rolls: attacks, skill checks, and saves. Each has its own rules and modifiers. Plus, there are "spellcasting checks" which are kind of attacks but also used for other things. This is messy.

Options:

Everything is a skill

So we need skills for:

Save skills:

We've been down this road before. We have to separate these "special" skills from normal skills, or the skill list becomes unmanageable. There are way too many of them.

New proficiency system

So you've got 6 ability scores.

As you gain levels, you add proficiency bonuses to scores of your choice.

You are "proficient" at everything you do, proportionate to the bonus.

Instead of skill proficiencies, there are skill feats that grant specific benefits.

Each level, you gain two +1 proficiency bonuses to assign to ability scores of your choice. They can't both apply to the same skill. This is a full bonus modifier, so in 5e terms, it's a +2.

Your starting Foundation also includes 3 levels' worth of proficiency bonuses to assign as you like.

Example: