This is a smart move by May (though some sources say it was the rest of the Cabinet who wanted an election). The Tories are 20%+ ahead in the polls. Even if they're out by 5% the lead is still 15%+. The media will be happy to carry the message "Labour in disarray" and "Corbyn unelectable" for the Tories as they have been doing since he became leader. The problem for Remainers is that the Remain vote is split over a number of parties, whereas the Tories will be going forward as the party of Brexit.
Expect the North not to feature, Laobour to do not as badly as expected (there are about 200 pretty "safe" Labour seats), Lib Dems are starting from a low base so will probably win a good few seats, SNP have nowhere to go but down, and why anyone would vote for UKIP now is beyond me. Tory majority of 75 - 100, then May will go forward with a mandate for what will turn out to be a soft Brexit. Remember where you heard it first!