If they aren't going to show Spartacus die, I'd rather they leave his fate ambiguous than to show him riding off into the sunset. He is fighting so hard for the cause, has lost many that he cares about to it. Even if/when he gets his ass handed to him, I can't see him fleeing to parts unknown with his tail between his legs. He would rather die in a losing battle than run away like a coward. And I expect nothing but the former or an ambiguous end to him when the show comes to a close. Anything other than that will IMO undermine the legend that is Spartacus.
Don't get me wrong I'd much rather see him die or get that ambiguous ending where he's most likely killed off (going out like how Butch Cassidy and the Sundance did)
I'm just saying I wouldn't blame the writers for choosing to give Spartacus a fate where he survives. After all in real history Spartacus and Crixus did split up, with Crixus wanting to continue the plunder in Rome while Spartacus wanted to return to the slaves' homelands. Some say the split was a strategy but there's no proof that's what the plan was. We're still early in the season and we don't know how Sparty will change.