Tier #5 ships are a thing of the past, we all know that now, and we're unlikely to get anymore of them - except for maybe the odd secondary Lock Box prize item. Tier #6 is the way forward, yet there are still some designs that haven't made it to the top that I would think have a place there. Lets examine;
I'll start with the Cruisers, specifically the Odyssey, Bortas and Scimitar. Whilst there is no certainty with these, I think it's a fair assumption that they'll be coming at some point, though I would request that ships such as these get something truly unique. What do I mean? Just mix their stats up a bit. A lot of the [cross faction] packs all seem to share abilities and such, and I can't speak for everyone, but I wouldn't mind a little diversity.
Maybe, with the three above, you could play with the new specializations?
* Provide the Odyssey with a Lt.Cmd Eng/Cmd, a Lt.Cmd Sci/Intel, and a Lieutenant Tac/Pilot
* Provide the BortaS with a Lt.Cmd Eng/Cmd, and a Lt.Cmd Tac/Pilot and a Lieutenant Sci/Intel
* Provide the Scimitar with a Lt.Cmd Sci/Intel and a Lt.Cmd Tac/Pilot and a Lieutenant Eng/Cmd
...or something to that effect. Other seating (and consoles) you can work to your discretion.
Then there's the Vesta; another ship that no doubt will get her T6 status. Maybe this ship could feature a seating setup that includes a Lt.Cmd Sci/Intel and a Lt.Cmd Tac/Pilot? Both the KDF and Republic are seemingly short on Science Ships too - and if I recall correctly, there was a livesteam where it was said there are no plans (or something like that) for any more Klingon or Romulan Science Ships? Probably because they don't sell too well (but who's fault is that?) needless to say, if you don't want to provide Klingon and/or Romulan Science Ships, how about Gorn, Reman or Suliban Science Ships?

I wouldn't also mind seeing a T6 Vulcan Science Ship (also available to Republic players?) and a T6 Andorian Escort/Raider. I'm sure there's multiple ships coming out before Season 11, I'm just hopeful that at some point, Cryptic will consider what I have here.