I'm definitely a pusher. If I have radiance I'm slowly walking with either a handy cannon or a pulse rifle and taking out as many little guys as I can with firebolt grenades. If I'm using voidwalker I do the same thing but stay back a little more and make one big push with a nova bomb. With that being said I usually go down but I'm always moving into the front and make sure I expend every bit of ability I have to taking out as many as possible at the front line. That way my team behind me can reach me without getting slaughtered and I'm back to plunging and taking the heat off of them. Voidwalker works well for that because with armor and recovery all the way up its easy to dig in and keep space freed up behind you for the rest of the fireteam to comfortably dodge the heavy stuff.