That is a fine goal to have, and as you have been made aware, that goes towards the whole "jack of all trades, master of none", which the game really seems to be geared towards modding as needed towards your focus.
I would give a suggestion though with the kits. Recognize what an ability strength is for. It doesn't sound like you do PvP. I know I don't touch it. And that is what confused me for a time about some abilities. Take Valk's harpoon (that is the WF that has it right?). I mean baring captures (and even then) it just seems worthless, esp with the shere number of mobs. Then 2 years into the game it finally dawned on me. That ability would be great in PvP compared to PvE. (I fully expect others to come to the ability rescue. You'll just be wasting your time, as I don't care. I don't use it. Make a different thread if you want to defend it, but as stated, I don't care.)
I get the idea of failure and fear. I really do. My mother was, I'll call it gently verbally abusive. As in she was never vulgar or directly abusive ever, and would typically sacrifice to make sure I got what I wanted. BUT... in my teenage years, she ended up with a catch phrase that utterly destroyed my self confidence over time. "If you are going to do a half ass job, don't bother doing it at all." So consequently I stopped doing a lot of chores, other than mowing the grass. I never had comments tossed at me about the mowing so I kept with it. Took me years to realize what happened, and 2 decades after that I still lack confidence in myself. (Thankfully a trait I got from both of my parents is being stubborn. So that helps me succeed in work.)
Just take baby steps. Sure they may seem insignificant, but take them. It adds up over time. Been there, facing that.
And FYI, most of the mods I always see players saying use? I don't have them, but I can solo the first Eidolon now. Go at your pace, but take the steps. You may find if you can start to make growth here, you can transfer that same confidence into outside the game as well.