Let's posit for a moment that Crassus is able to not just win decisively at Carrhae, but string several additional victories along his march east.
1. With Parthia in the factured state that it was at the time, could it have survived such a campaign without collapsing into a variety of successor states?
2. If does collapse, how far could Crassus push his conquests? Could a Roman Babylon be a plausible outcome?
3. What effect would an even richer, battle-experienced Crasuss have on the stability of the triumvirate system? Could we see Caeser and him teaming up against Pompey?