From a budgetary standpoint I haven't noticed a drop in quality. Heck it seemed like the move to Vancouver might have helped the show (even though I really we we see Cat again before the season is out).
Yes -- apparently the network license fee and the costs of filming in Los Angeles were so high that the savings from the move more than offset the budget cut for season 2, so the show actually has
more money to spend on what actually gets on the screen, like sets, props, stunts, effects, etc.
I do feel some things have been lost, though. No Cat, no Max Lord, no Lucy or Sam Lane, no Noonan's. Cat was given a reason for leaving, but Max and Lucy both disappeared without explanation, along with DEO Agent Vasquez (although I've seen that she's returning in at least one episode later this season).
And shooting in LA gave the first season a distinct look from the Arrowverse shows, but now it looks just like every other Vancouver show. The National City helipad where Superman and Supergirl saved Lena Luthor had exactly the same skyline behind it as the Central City rooftop where the assembled heroes fought the Dominators at the climax of their invasion. And President Marsdin signed the Alien Amnesty Act in front of the same geodesic dome that served as the Time Masters' Oculus in
Legends of Tomorrow. And let's not get into all the different places the Vancouver Central Library has shown up. (It's literally across the street from that aforementioned rooftop/helipad, by the way, and just a few blocks from the stadium used as the exterior of STAR Labs.) I'd been hoping they'd use digital skyline replacement (like they used for the CatCo rooftop scene in the pilot where Kara revealed her secret to Winn) to give the Vancouver locations they used more of an LA/National City look, but they haven't.
