Most of the TNG cast are in their sixties by now. Even if any of them are still in Starfleet, they likely have desk jobs now.
I really don't have a problem with them having retired. Granted, it would be nice if someone from TNG cast was still in service. And yeah, I guess it would be super cheesy if Captain LaForge and the Enterprise would arrive to Deus Ex Picard and the gang out of some space trouble, but let's be honest, most of us would still love it.
I have no issue with leaving the Enterprise and any other 24th century characters on the sideline for the entirety of Picard’s run.
I'm going to laugh boisterously if it's a different design then the one in the novels. And then I'll go down to the Trek Lit forum and feast on the fanboy tears.
One of the things I love about PIC is that it's showing that there is life beyond Starfleet. I'd really like it to be a case that Riker & Troi simply retired because they had done their bit for king and country and now wanted to do other things and enjoy life. No more duty shifts, no more Starfleet regulations, and no more tight uniforms to wear every day.
Riker grew up in rustic territory, being from Alaska. Maybe him and Troi wanted that for their children?
I'm starting to believe that their home will be in Alaska. It's no secret that's where Riker was born and grew up. We might even get a framed photo of Kyle Riker in their house since Will somewhat reconciled with his father in Season 2 of TNG.
I hope Lwaxana is still alive even though she obviously won't be appearing due to Majel's death. Picard's reaction to the sheer mention of her name would be funny.
Is Carel Struycken still alive? Mr. Homn can always have a cameo and it can be inferred that he's delivering something for Lwaxana since she can't personally visit her daughter, granddaughter and son-in-law.