Happy if I can be useful in any way at all
Style wise, honestly, I don't think you should limit yourself too much. I like what you did with Desperado and what you did with True Colors, and they are fairly different songs. What you seem to cover is mostly pop, so you don't really have to choose as the technique would be the same for these songs - it's not as if you were hesitating between classical and black metal
And you have a recognizable voice so you superimpose your style on all these songs anyway, which is pretty cool.
What I'd say is: try to pick songs that don't force you into falsetto (because it's hard to use properly and can sound disconnected) or down into the two or three lowest notes you can hit (because you seem to almost always get pitchy when you sing them). It limits your options a bit, but this way you can concentrate on getting your pitch and your "regular" voice right before exploring things further.
If you feel that you have issues with voice strength, the single most useful thing I've ever been told is the following:
Put your hand on your belly right below your bra, in the soft spot between the two halves of your ribcage. Now shout out "hey" as if you were calling at someone far away. You should feel a muscle tense under your fingers. That muscle is your diaphragm and it should be engaged at absolutely every moment when you're singing. It is what gives your note sustain and strength, and also control: you will have a hard time staying on pitch if your diaphragm messes around (I know that first hand, it's one of the issues I am trying to deal with atm
) On the other hand, your abdominals should stay relatively relaxed.
I'd like to reiterate that, having heard your covers again, I think your "regular" voice has a great timbre. If you fix your pitchiness issues and find someone to help you ground the extreme ends of your range, I think you'll be an absolute pleasure to listen to.