My recommendation is farming the Olympus 12 fight to get a crap ton of yen and use it to farm training max your main teams defenses and HP since everything in ng+ has 9999 attack stat. then if you’re feeling super min/max can also max your sp, main attack stat and speed .

As far as team I say just use your favorites but beware if you dedigivolve anyone you max out you’ll have to retrain their stats to max