There's a lot that is answered here, and some good possibilities for robust mechanisms.
(1) Tool Proficiencies are great for those skills that should just be on/off. Riding horses and climbing fell here in the last test pack, and I'm fine with that. The absence of swimming from the list suggests (rightly) that it too might become a tool proficiency. I'd like that a lot. At the point that it becomes interesting to roll, being untrained really does mean failure.
(2) A short skill list with 1 STR skill, 3 DEX skills, 3 CHA skills, 6 INT skills, and 4 WIS skills (with the acknowledgement that there are situations where a roll makes sense not using the primary ability).
Indeed, I'd pare it back further:
--> there is no need for Athletics: a straightforward STR roll should be fine. (GX.Sigma suggests as much just above)
--> there is no need for Perception: a straightforward WIS roll should be fine. This will also fix the problem of giving elves enhanced senses, which means that other characters can never catch up. It's so unhelpful, and it's not like elves are hurting for abilities anyways. Further, it is a skill that is rolled constantly (unlike the others), which makes it a skill that players need to invest in if they can, effectively reducing overall choice. best not to have it.
--> there is no need for Performance: that's not actually true, but the ability to perform and entertain is already being covered in backgrounds and (potentially) in tool proficiency. Adding a third mechanism for how well you play the tuba seems unhelpful. And it should be the skill (which scales with level) that goes, since it is the one that scales with level. The game is never going to model child prodigies or whatever well, but we know that measuring it as an on/off available at first level, or as a background trait to tie you to the surrounding society is more representative than this sort of skill system. The redundancy needs to be addressed, and this feels the best way (based only on the generalities in the article, of course).
--> is there a need for search? A basic INT roll should suffice on its own, I'd have thought, when working at this level of granularity.
(3) Some thoughts on Knowledge skills (History, Arcana, Religion, and Nature).
--> A lot is being rolled into history: heraldry, court-etiquette, military strategy. This will get rolled a lot, I expect.
--> I think there should be a skill for "forbidden lore" -- something about the other planes etc. requiring a separate set of knowledge than Arcana or Religion.
--> The absence of a dungeoneering skill is also a significant design choice.
--> there should be a means of knowing things about certain cultures/races. The last testpack had that in Ranger abilities (dragons, or goblinoids, or whatever). But it should be possible (and again, tool proficiency's on/off mechanism might be appropriate.