Companion Druid Viable?

New to D4 (only did a bit of the betas). Got the standard and will probably hit the ground running from this weekend. I would love to do a companion build and thought of druid since I spent too many hours on D2 with my necro fishymancer build.

Is a companion build doable long run in he higher difficulties? Also is the playstyle more of a support spellcaster or primary melee with companions supporting? Thanks for any tips and skill advice.