I haven't had too much time to think about this but ill try. So let's start:
10. Sweet Memories. It makes leveling up master form take 5 minutes. Cool stuff.
9. Star Seeker. I switch to this from the kingdom key after Land of the Dragons always. A solid keyblade that gives me the useful early game ability of one extra hit in the air.
8. Hero's Crest . It's a keyblade I usually use up until I get another keyblade coming up so I have a ton of experience with this one. Very useful for most situations and I can rip up data Xigbar on Critical with it. I'm not a big fan of the overall appearence of it.
7. Oathkeeper. Mostly used to level up my drive forms. Makes it way easier and overall this is a decent keyblade.
6. Fenrir. A very solid keyblade that has immense power and allows me to get those finishers out faster. I hardly use it but it's quite decent.
5. Winner's Poof. With crazy magic damage like this you can simply tear through enemies. I absolutely love using this thing and wish I could find more situations where it is useful.
4. Rumbling Rose. This is usually the point in the game where I switch off of Hero's Crest. Being able to completely dominate with finisher after finisher is extremely good. The Keyblade overall has great stats.
3. Bond of Flame. Mixing this with Final Form and Firaga will completely decimate anything in your path. Extrememly powerful.
2. Photon Debugger. This + Magnega + Thundaga = Win
1. Decisive Pumpkin. Absolutely DESTROY everything with this keyblade. Once you get it you never go back. Truly the ultimate weapon.