Guys, I've gone back. Turns out you can get Reddit revanced and remove the ads/promoted posts so I'm fine with the Reddit app now. I'm kinda using both but there's just so much more content on Reddit.
Then uninstall the play store Reddit app if you still have it. And install a version of Reddit from here I believe you want a bundled version but it'll tell you if that's wrong when you try patch it with revanced.
Finally open the revance manager and find Reddit, click the patches you want - it's quite limited still and you'll probably only want to select the remove ads patch but have a read, there might be 2 or 3 you want. If there's an error try downloading a slightly older Reddit apk.