The time travel thing I think could get a bit too complicated / not make sense, to be honest... it's really problematic. Why would everything have happened exactly as it already has other than a few key points in Flash itself? For example - there have been many crossover concepts between Flash and Arrow... from Barry saving them on occasion, down to little "mentioned" things like Cisco making Black Canary's sonic device. If the whole flash universe has changed... would Cisco have made that? If he didn't, was there ever any Black Canary? If not... why is Laurel Lance now dead in Arrow?
HOWEVER - don't know if we all watch Legends of Tomorrow - but there's going to be crossovers AND in the finale last week, the closing scenes involved them discussing how the Time Masters were now gone (the people previously responsible for keeping time intact, basically wiped out by the Legends), the Legends of Tomorrow team would now have to take on that responsibility... so, will we see crossovers where they have to take responsibility for making sure that all of the major "anchor points" in time that have now been screwed up by Flash are kept in order, and everything ends up as it should be or as close to it as possible? Hmmm. Also Legends ended with a member of the Justice Society (sort of a precursor to the Justice League) crash landing from the future to tell them about some major **** going down. Caused by Barry upsetting the timeline, maybe? Also, Supergirl is moving to the CW for S2 and is merging with the Flash/Arrow/Legends universe permanently (Flash went to Supergirl-world for one Supergirl episode last season, accidentlly hopping dimensions when he was testing the Tachyon device). Part of this Flash-time-reboot could maybe explain Supergirl now having access to Earth-1? I think they'll keep her world in general separate to it, becuase otherwise they have to say that Superman is now active in the Flash universe, which is a whole can of worms as they can't actually cast or use the character due to licencing issues. Basically they can only "hint at" Superman and Batman, they can't explicitly use them, e.g. I think someone mentions "That other guy... in Gotham" in an Arrow episode and in Supergirl they mainly make vague referrences to "her cousin" without him ever appearing other than an occasional glimpse.
Thinking about it though, pulling Supergirl (and maybe the whole of National City?) into Earth-1 would be a good move for that show as it eliminates that issue. Superman would be left back in his own world, and Supergirl would now be the only Kryptonian on Earth-1. Solves a lot of problems really. Maybe even hinted at with Zoom talking about "merging universes" and Earth 1 being the focal point? Hmmm...
Anyway... I do agree that it's a good bet that "real" Earth-1 Harry will be the "new Wells" next season, with Barry stopping Thawne in the past now meaning that he won't kill and replace him. That could be interesting - would be a sort of fun tradition to have Wells be in every series but a new version every time :joker: