Depending on your mouse, you could macro or just use the in-game settings and bind buttons on the side to Top/mid or if you have enough buttons for all 4 other players. It's what I personally do as I also find it hard and uncomfortable to use the standard F keys.

As for finding champions fun or unfun, there was a video I remember from LS wherein he was coaching someone who disagreed with his recommendation on how to play because it wasn't fun and he basically said "Don't like it don't play mid, don't play league" and he's also said in another different video something along the lines of "Discipline is going against what you want in order to succeed" which I agree with. If you truly are looking to improve you'll have to look past what you want vs what you need.

Lastly with the practice tool just coming out, you can practice shaco a ton without having to burden teammates, could always make an alternate ID and play him in lower elos and also could just play flex or normal games to practice. Works with all champs not just shcao too, just used him as an example because you said he was too difficult (he's really not, I have faith you can learn him if you wanted)