It looks like you have carved out a stable, and viable kingdom of your own.

Have the Getai even bothered to send small armies to you? Thy might have, since they do not share a border with the Sauromatae. Economically and strategically you have little to gain from the Getic lands (other than wiping out the sole threat at the northern border). But as Naissos is still not under Getic rule, the only place that is under any sort of threat is Singidunum. Taking out the Getai would have merit if you'd try to take Kallatis, Tylis and Byzantion, before venturing into Asia Minor. Mind you that the Eleutheroi controlled areas will suffer from limited population bases as well. But that is more of a long term plan for you (if you can avoid a conflict with the Sauromatae that might be the result of expanding in that direction).

This consolidation phase may well start with attempts to isolate future / current enemies diplomatically, building up navies if they have a role to play in the forthcoming conflicts as well. One idea would be to form an alliance with the Kart-Hadast against the SPQR. Role-playing wise, the new King may actually want to establish complete control of the Greek lands, and thus weaken Makedonia diplomatically. The Makedones, without support from either the AS or the Ptolemaoi, might be a tempting target.