I think for your first run with these kinds of games, you should stick with the choices you've made. This is the "canon" of your run, in my mind, where choices are made in the moment with no more knowledge than presented. If you're playing these games so you can get the "bestest" result, there are games that'll do that better than choice based games.
In my first run through, I had Ashley and Wrex killed, and I never even bothered to do the side missions about Cerberus, EVA or Garrus. Second playthrough, Grunt and Mordon died. However, I got to see Wreave and the replacement Krogan and Solarian who I don't remember, and it felt my choices mattered more.
Honestly, what I found most disappointing about it was when I replayed and saw just how little difference there is, kinda shatters the choices illusion. Same with Telltale, first time I played was magical, and then I realised that if there is an option for someone to die, then that's it. That character may as well cease to exist and they'll get killed off as soon as possible.
Back on topic, I'd say don't restart. Play this through, and then replay it with the foreknowledge of how to not fuck shit up.
In my first run through, I had Ashley and Wrex killed, and I never even bothered to do the side missions about Cerberus, EVA or Garrus. Second playthrough, Grunt and Mordon died. However, I got to see Wreave and the replacement Krogan and Solarian who I don't remember, and it felt my choices mattered more.
Honestly, what I found most disappointing about it was when I replayed and saw just how little difference there is, kinda shatters the choices illusion. Same with Telltale, first time I played was magical, and then I realised that if there is an option for someone to die, then that's it. That character may as well cease to exist and they'll get killed off as soon as possible.
Back on topic, I'd say don't restart. Play this through, and then replay it with the foreknowledge of how to not fuck shit up.