New to the game, need infos and help with my team!

[Aika]

I did a double post, sorry -.-''

Hi, i joined the game 3-4 days ago and this is the state of my team:

Now, i need some informations, if you mind :X, i know that Yuna is C rank in the tier list, but i don't know what it should be better for me right now since i did she 6* and with 6-7 -cost.
I'm okay with this team for now?
I bought even the 3000 medals pack so until sunday i can join every dungeon i want, do you know if there is some unit worth to be farmed? Maybe Water Sora final form? There he is in this version? (i didn't played the JP, just readed some post).
I'm working on a fire team too, with the Treasure Trove, where i'll use KH Riku, Hercules (since i've many), KH Riku Black Coat, DiZ and Goofy/Wakka, is it good?
The question i want to know most (and i already asked once xD) if i can farm some units 1*, can i?

Thank you in advance for all the answers.

 

[luvthe_gazette]

Check the walkthrough thread. Post #1 is very helpful and even though people have been playing the jp ver up until page 90~ their tips are still good for the na ver.

A while ago I made this masterlist of useful links (bottom half of post #1) you may find usefull if don't want to skim through the walkthrough thread.