When I started trying to improve I used Wizards (one for driving, one for putting), a Comet, and a Leopard. I had a Teebird but knew it was too much disc for me. I also had a Buzzz that I also knew could take some OAT so I put that away too. I'm not saying you have to go this route, but it worked for me.
I would go into the field and throw nothing but a stack of Comets for hours, looking like a total idiot. I hated how they felt in my hand and would always release them with tons of wobble or on an unintentional anny line. I couldn't throw a smooth hyzer to save my life. I also couldn't throw my Wizards very far. I'm talking about throwing these discs around 150' in a field (sometimes well populated, for an extra dose of shame for motivation).
I kept on throwing those Comets until the grip started to feel natural. I played putter only rounds at a pitch and putt, then at my home course when it opened back up for the Spring. Now I use my Anode for most holes up to 275' and my Comet or Buzzz up to 325'. I still use the Leopard and Teebird, but I've started to add some faster discs too (flirting with some different warp speed drivers for those 375'+ holes).
This is all to say that if you practice, you'll get there. Find some discs and stick to them. If they feel uncomfortable, throw them until they're not. I switched from a power grip to a fork grip and that helped, but it doesn't matter. Also, my hands are the same size as my own mother's and I can throw a putter, Comet, Buzzz, Nuke--it doesn't matter. Just practice through it--after all, when you first pick up a golf club you're not going to be comfortable, and until you've swung that club many times you won't be comfortable. It's the same with disc golf.
But don't forget to play your game on the course, have fun, and beat your friends.
If the Pure and Teebird seem like a great idea to you, do it up! maybe add a mid that's stable or at least an understable driver that you can power down on for when your Pure just won't quite do it.
