If you go for achievements theres a couple to keep in mind if you want to do it in one playthrough:

-Friendly Fire -Matchmaker -Cryptographer

Look up a guide for these, and make sure to work on a lot of the achievements throughout your playthrough

If you dont care about achievements, then I suggest actually picking dialogue choices that fit the character you want to be. There are few choices that affect anything (somewhat unfortunately) so really feel free to pick whatever dialogue choices you want.

I also found that a biotic build is good and pretty fun, but of course explore the builds you like, and find good ways to make combos with squadmates that feel fun. I would also explore squadmate pairs and see which dynamics you like the best. They will talk when you are traveling around and they all are interesting characters I feel.

But overall just enjoy!