Then your question has been answered empty yoru cup. Every dojo you go to will do things a little different, even if you were changing Aikido dojos. Start open minded and learn what the Instructor has to teach and don't reach back to your old ways until you are home.

In the end you must use what you can and discard what you can't but starting new you don't know what that is, empty your cup. All this is phyiscal and mental resist your ego.

Tennis and racquetball, i've heard hard to do both. Having moved from rather hard style karate, into not just Aikido, but Ki Society Aikido I know you will have advantage...but if I take it correctly previous practice was Ju-Jitsu then disadvantage will be need to go slower than perhaps you wish so as to avoid injuring unwitting partner. Go slow, more flow, and as The Founder Master Uyeshiba emphasized, Aikido is Love, to find and give "Abundant Peace". Good to know how to separate muscle/tendon/joint in nikyo, very good to know how to bring to ground or submission using nikyo w/o maiming.