I'm certainly participating on OFI vs. Panserraikos, firstly because it's my team and secondly, because the odds are quite decent, I'd also consider AEK vs. Panetolikos, the odds aren't anything special thought, and I also might take my chances with AEL vs. AE Kifissia, two new teams that we haven't seen perform in the new season. The odds are decent, so it's worth a try.
Personally, I will choose to bet on goals in 3 matches. Aris vs Panetolikos (more than 1.75 goals), Volos vs Olympiakos (more than 1.75 goals and a win for Olympiakos), and AEL vs Kifissia (more than 1.75 goals). Hopefully, this small parlay will give me my first Greek Superleague win for this season. Tomorrow is another story. I will wait until then to decide what and to which match/team I will bet.