If Greece made Euro 2016 , Tziolis would actually be useful. Since Maniatis is injured, we need someone to do the dirty work of DM.
As mentioned before, Tachtsidis and Samaris play a similar game.
As an idea, Torosidis might be good a CDM now that he's losing his pace. Much like Lahm is doing for Germany.
Samaris might be a better LB than Stafylidis when Holebas is out.
I don't know much about Petsos, but from what I've seen, he is very impressive.
I feel that he's a bit isolated being native to Austria - Similar to how Holebas was.
Playing in the superleague or a higher quality league than Austria would up his pecking order.
I rate the Greek league higher than the Austria big a considerable margin.
In the past the (2010 for example) we were just behind portugal, 7th best league in Europe)
Now we're around 13th (just behind Turkeys league)
Austrias probably like 16th - slightly better than Cyprus.
http://www.uefa.com/memberassociations/uefarankings/country/
It's run very well because it's somewhat like how the Scottish league is to the English League.
The Austrian league is like a minnow league of the German league.
Despite the Greek relative laissez faire attitude, the quality has always been there.
Berg, Cisse, Rivaldo, Galletti have spent some great years in Greece.
As well as our domestics Manolas, Sokratis, Karagounis, Katsouranis.
It's a great league. Olympiakos beating Arsenal & Paok Tieing Dortmund last week are testaments to it.