My hairline is very very similar. I also have similar straight hair. Curly headed men seem to have a leg up on covering temples whereas mine (and it looks like yours as well) hair grows straight forward. It's hard to sweep to one side without exposing the other temple worse.
With all of that said, your forelock is still pretty wide, which by the norwood scale isn't always the case and it still looks pretty good imo. I've been on finasteride for about 15 months and maintained pretty well. I think you are doing the right thing, just keep on the path.
Best of luck to you