Imho the change of Mythic Improved Critical is not the right direction

[Predictabowl]

I know that balancing Pathfinder tabletop system is a fool's errand (even if is better than D&D 3e, is still way too broken), and I agree that the original Mythic Improved Critical is kind of busted, but the actual version (as of 1.2.10) that add a static amount (albeit random by dice rolling) per attack is very skewed in favor of styles that use many attacks, leaving 2 handed weapons in the dust, and is totally worthless for ray spells.

A better an alternative, I don't know if is possible with the engine, it could make enemy take +25% more damage against the attack that crit (or make him vulnerable, but +50%, is way too much).

Another one would be, instead of a fixed dice (right now is 3d10 per crit point), to take into consideration the base weapon damage, for example 4 times the base weapon dice, so a rapier would be 4d6, a longsword 4d8, a greataxe 4d12, and so on. This won't solve the issue with ray spells tough which would need a lot more than 4d12 to make it viable, without even considering that fixed dices weight a lot more on low level spells (like snowball and scorching rays).

[Vek17]

The intent is to reduce the power of the feat relative to crit range of the weapon, and make it not disproportionately benefit high range weapons. The current concept is modeled after burst enchantments and how they scale as a sane starting point.

Ray spells RAW arguably shouldn't benefit from the feat at all anyway so it is not an area I am super concerned about.

[Predictabowl]

Yes, I noticed that is modeled after the burst.
If making it worthless for rays is your design choice then let's ignore that.
Still is a mechanic that is good for 2 weapons style and bad for 2 handed (like burst), in that case taking into consideration the weapon base damage (not the crit range) would make it a bit more even (even thought the weapons itself are all over the place anyway).

I would like to disclaim that I'm not asking for a change or anything, I'm just pointing this out just in case it was not considered.

Lastly, good work on all the mods (especially the option to be able to select which one enable individually), they made play this game bearable for me, so thanks a lot.