I opened the files for skills on humans and giants, and if I'm reading it right then currently giants have a load time of 1.6s at r1 and dan 1, with 600% dmg that goes to 640% at Dan 1; humans are 2s load time and stay at 500% if I read this right. So your changes would actually be a nerf to giants I believe? Anyway, this and shield charge are your basic highlights for being a giant, so be very
careful about bringing humans and giants too close here. Buffing giant's smash splash damage would be something I'd get behind though.
Magic: Giants are supposed to be bad at it was the original concept. I'd honestly support humans being your base, giants having less damage or higher MP cost which we do for int magic at least, and elves having basically any kind of buff on it. Be very careful on increasing load times, because this will affect the rhythm of combat, I would not be happy as a giant to suddenly discover I can't bolt counter a Sahagin or something anymore. Similarly increasing load times of int spells, which are already horribly slow, would be very very frustrating.
Life skills and similar production related like Alchemy Mastery and such: I'd actually be okay with racial bonuses on those too. Tbh, I'd love a higher focus on crafting, making it feel more rewarding. But as an example, giants who are a str oriented race would be better at something like smithing, give humans tailoring, elves alchemy boosts for magic relation... More brainstorming than presenting a detailed idea, so don't take this part too seriously.
Other stuff I don't have much of a strong opinion on.