Yeah the post-20 grind can be discouraging. Do daily and weekly stuff (and the higher level you can do it on, the better the reward) for a chance at good gear. And do Vanguard strikes for Vanguard marks, which you can use to buy pretty good purple armor at rep level 2. If/when you do start getting Crucible marks, consider picking a faction (I like Future War Cult because their armor focuses on Intellect and Discipline) and getting to at least rank 2 so you can buy their armors.
In the end, though, Destiny post-20 is a grind no matter how you slice it. I enjoy the gameplay so the repetition doesn’t bother me TOO much, but I definitely wish there was more content in the game.
Oh, and if you ever get to level 27 or 28, I highly recommend trying the raid with a group of buddies (or people on destinylfg.net). If you’re on Xbox One I’d be happy to do it with you if we play at the same time, but as a mid-30s father of 2 myself I’m not sure how likely that’ll be! But yeah, the raid is probably one of the most interesting, challenging, and rewarding parts of the game. It’s a shame not everybody will get a chance to experience it.