I didn't have a problem with Riker and Troi being in the episode, but it was poorly executed.
What I would have done:
-Have the episode proceed as normal, no Riker or Troi in it.
-At the very end, after Archer gives his speech, we zoom out and Riker is watching it on his laptop thingy, he has not been watching the whole episode obviously, just the speech.
-Troi comes in, says are you ready.
Riker and Troi leave Enterprise E and go to Titan, Riker says something like "There will always be something magical about the name, Enterprise" or something less cheesy
I know it probably doesn't make that much sense, but it would have been less of a slap in the face than what we got. And left it open for a possible titan series down the line.