Hello,
there are many 'support' classes in Allods, and most classes have a support aspect,
however 'support' does not always mean they can be good offhealers, it can be related to cc or buffs etc.
What you have described seems to fit the druid class. Druids have pets, can be dps, offheal and full healers.
Summoners also have pets and are very good dps and offheals, and are very strong.
I haven't seen many summoners going full heal, but i think that is possible too.
F2P server is the most populated one as it's the original server.
However you might enjoy the P2P server more if you are new players and don't want to compete
against all the strong veteran players.
Overall
a) i think Druid fits,
b) you can try both at the same time if you are in the mood, and stop playing on f2p if p2p is your server of choice