I'm looking for advice on a post rotation deck that I can't build
Any advise on deck types and good cards would be nice
Thx
Post rotation I'm assuming you are referring to rtr and m14 disappearing. Not all of M15 has been spoiled nor the following set.
So it's hard to speculate but as previous comment stated in the block constructed BUG did well and constellation decks are doing decent atm to an extent. It's hard to say how effective it'll be without {mana blossom} that card makes constellation triggers insane.
As {courser of kruphix} underestimated on release has sky rocketed from ~$2--$16 currently and a hexproof sylvan stonewalls most aggro decks and were integral parts of most block top decks it's safe to say these cards will maintain their value opening the door to G/x decks as it stands.
I also feel the devotion mechanic may be more viable as it's somewhat a theme with journey cards. And the dictates/new m15 appear to want to scream mono decks. It's all up in the air for now!
Hope this helps.