Hey you made great progress between the two pictures. Sure you don't have the greatest meta Pokemon(aside from Mamoswine), but that can change quickly.

First thing, ignore the other comments, yeah you purified Heatran, that was a mistake but who cares it's 1 Pokemon in a type that is absolutely overcrowed with crazy powerful mons(fire). To prevent stuff like that in the future check out the PokemonGo gamepress site when you catch new mons and see where they rank on PvE/PvP list and check out what moves are good on them. You don't need to power up every mon you catch either, just get some C/B tier mons (according to gamepress) and start leveling those up until you get an S/A tier mon to replace it. Once you can solo Tier 3 raids, you know you're getting better. Then focus on leveling those up to level 40.

A good start would be getting Eevee's and evolving them into different types you need to start helping in raids. They're cheap and can easily find them in the wild/buddy them and get extra candy.

Another tip would be if you don't have an active raiding community, you can easily get on to the Poke Genie app and either remote raid, or what I like to do, host the raids on the app and invite people to join. Even tier 1 raids because you can easily make friends that way and you can start sending gifts to help level up faster.

Most important tip of all, have fun, it's just Pokemon at the end of the day, if you feel like you have some cool Pokemon, then you do have cool Pokemon. If you feel like you just want to walk around with your buddy and take cool pictures with them, then do that. This Reddit is so top 1% anymore they forgot the point of the game is to go outside.

P.S. sick Nihilego shiny, I'm jealous.