DeviousQuail
Hero
Mostly focused on Points 2 through 4, just spitballing some ideas:
- If you implemented 2d10 you can make a rule that when you don't have proficiency you only get to roll 1d10. Or avoid 2d10 and just do d20 for proficiency and d10 for no proficiency. This should give those with proficiency a massive boost over the non-proficient without changing anything else.
- Expand the range of proficiency "tiers". You could go with none (no bonus), half (half bonus rounded down), proficient (standard 5e bonus), expert (x1.5 bonus rounded down), and master (x2 bonus). The only one of these that doesn't already exist, that I can think of, is the x1.5 bonus. And if you hate it you can just replace the x1.5 with something akin to the rogue's reliable talent ability.
- Whenever you get an ASI you'd also get to do either 1) adjust two skills from no prof to half prof or half prof to full prof 2) adjust one skill from prof to expert or expert to master.
- Instead of an altered progression you can just make proficiency start at +4 and end at +8. This should make conversions easier for players and NPCs because all you ever have to do is add 2 to proficient checks.
- To give levels more weight you could add a second "level bonus" alongside your proficiency bonus. Your level bonus would start at +1 and increase by 1 every time your proficiency bonus increases by 1. Unlike proficiency bonus, the level bonus would affect everything (saves, skill checks, initiative, AC, attack rolls, damage rolls, spell attacks, spell save DC, etc).