Agreed. I like to think that because the last line in the script talked about "possibility" that O/F might have a similar life with their loved ones in whatever dimension this is. Maybe the office scene was just him greeting her before taking her out to show her the world.
It's not the ending that I wanted for Oliver - I wanted nothing more than for him to come home to his wife and kids and get to spend the rest of his life with them, but since I apparently never had even a sliver of a chance of getting that, this is satisfying for me. The only alternative to it was Oliver dying and staying dead with no hope of anything close to finding happiness in another dimension or wherever exactly he is. Felicity called it the "afterlife," but who knows if that's what it really was or just what she called it.
Plus, it's helpful that we know The Monitor can be wrong - he was wrong about how Crisis played out, so maybe Felicity *can* return to Star City from wherever she and Oliver are. There was no body left over when she walked into that smoky hole thing with The Monitor so it's not like she died in the traditional sense. Plus, MG said that Oliver is still Spectre and left open the possibility of him returning, so it seems like he can leave wherever it is that they are. Maybe when he does he can take Felicity with him.
Regardless of the fact that I would've done things differently, it was nice to see Oliver so at peace and happy. While bittersweet, I found the last scene and the idea behind it to be achingly romantic, and for a show that made me angry so often, that's a nice feeling to part with.