It would ruin this games main feature, that your character is what you do, your choices etc.
You can start a new char if you want other skills.
No, it really wouldn’t ruin it. There’s exactly no reason that you need to use it if you don’t want to.
The issue here which I think you might not completely understand given your posts, is that there is zero indication of a level cap until you hit it, and a lot of the skills sound either very good or near useless but aren’t.
I encourage you to look at the aim speed skill as an example of this. The exact wording of the description is ambiguous, the actual effect is largely useless you really want to go around quickscoping everything (which is largely pointless BTW), and the possible alternate meaning for the description is something that would actually be useful. All in all, it’s a trap for new players, and if such things exist, then you should be able to respec without having to relevel. The issue here is figuring out how to limit it so it can’t be abused, but that can probably be easily done by putting a 12 hour (real time, not game time) cooldown on the ability to respec and forcing you to go to Yttervik (or a command bunker, or some other predetermined location or set of locations).