R2 Adv droid will only hold 5 total modules, there are 6 Ent effects modules plus the playback, that equals 7 modules. There are no droid models that will hold more than 6 of the 'general' modules.
The R3 Adv works well for Entertainers, as it holds 6 modules. Skip the Electric fog and Foam, as these are annoying and cause lag for other players, that leaves 4 effects and you can add 2 playback modules or 30 item storage.
Socket clusters can be somewhat confusing, as the descriptions in game are not all that clear, ..you will use 2, Socket cluster- Combat and General in the R3 Adv.
Entertainer modules do not need to be made from quality resources, nor the droid for that matter ..and do not put armor (defensive module) in the droid as it will not show, unless the droid is made for combat.
kk, looking at this post, I seem to have rambled a bit, I hope you can make sense out of it, if not I will try to elaborate