I’m using AL-chan, which is a frontend for anilist.co. Of course, there are various other frontends available, including just using anilist itself directly.

My biggest gripe is it doesn’t let you know when new episodes are out for anime you’re watching

AL-chan does this

I also don’t like the numbering system for watched episodes - it starts at zero instead of one so it shows the last episode you watched vs the next episode you should be watching.( It’s relatively minor I know but that’s how I prefer my show tracking)

I’m guessing you’ll have a hard time finding an app that displays the number of episodes you’ve seen +1 instead of just showing the number of episodes you’ve seen. As far as I know, AL-chan can’t be configured to do this.

Features it does have that I need are displaying English titles

This is configurable

the ability to rank series (even if it’s just locally).

No problems there either