The first route, Cass route, is now complete.
Despite there being 2 more routes, the game is now 50% complete (hence 0.5) in total since the second and the third routes will share some events with Cass route, which is mostly Viviant’s events.
Cass route is the least involved route, meaning this is the most peaceful one. The second route (Aurora) is the most bloody one.
The final battle has two variants because you are given a chance to kill Kleon earlier. So, the final battle has two variants, one with Kleon and one without.
As mentioned in a previous patch note, Cass route itself has two more variants. Go all the way with Cass, you will get the true ending. If not, just a generic ending.