A very blah finale to a season that became damn near unwatchable after the prison arc, imo.
In theory, I'm ok with Oliver going out in Crisis (better him than Barry and Kara!), but the thing that doesn't sit right with me about it is, you have to watch the crossovers in order for that to make a lick of sense, as it otherwise doesn't jive with the the stuff that normally happens on Arrow at all. Like, up 'til now, the crossovers have been kinda their own thing, vacations from the main plots of these shows, and you could take or leave them as you preferred. But they had very little impact on the shows themselves. So if you take Arrow as a series on its own, as a standalone work, and watched it to see a vigilante show and didn't bother with the crossovers, you're getting an ending that is much more in the Flash/Supergirl realm of cosmic fantasy that makes very little sense for Arrow the show whatsoever. Now, I'm personally fine with this as Flash/Supergirl are my Arrowverse shows of choice and watching this one has been a bit of a chore for me more often than not, but I can't imagine this ending will be at all satisfying to those who've been watching from the beginning and have always preferred Arrow's "grounded" tone/approach over the others. And it seems to me like Arrow's finale should be made for fans of Arrow, not the Arrowverse at large.