Fun, but needs better CGI I was very excited to see The Flash as a massive Keaton/Batman fan. Lately, being excited to see a movie has usually left me disappointed and have to say the opening sequence left me worried. I like the 'fun' side of The Flash but it was borderline silly and the CGI was not good. I stuck with it and have to say it did bring me back in.
Miller, setting aside all their off-screen issues, does a great job. In fact the whole cast, without exception give superb performances. Keaton's performance and his story were the highlight for me.
Some multi super hero movies have felt like they're cramming in too much complex plot and end up being messy and confusing with a feeling of being overly long. But I felt The Flash did a great job of keeping it simple, considering it tackles time travel and multiverse.
I like the dark stuff in DC, so I had to accept this was going to be more tongue in cheek and fun, just accept it don't think too much about technicalities or plot holes. It's supposed to be fun and it's multi-verse time travel - let's not get overly bogged down in 'well that wouldn't happen'
Some of the CGI seemed unnecessary, so when it was bad I wonder why they bothered. Just keep it practical. My biggest criticism is the CGI - it risks taking you out of the film when it doesn't look good. But stay for the plot and the performances.