So maybe then Gladiator Games are what they are and the lack of tabletop movement has to be there.
This exact problem is what prompted me to try my own hand at a set of gladiator rules. There is a lot of movement in Blood on the Sands, admittedly a "push back" mechanic after an attack, but it does force the players to try and keep their gladiators away from the wall. Placing objects (pits, pillars etc) or even fallen weapons in the arena makes this jockeying back and forward important and hazardous. Also a flanking attack will spin the combat around and is a good tactic to try and position an opponent where you want him.
As for it's solo playability - that's yet to really be seen.