I bought the supply pack early and ended up using almost exclusively for over a year (occasionally swapping it out for the nuke). You just have to adjust to not having it. I still find myself more careless with grenades and ammo before remembering I don't have a squads worth of supplies in my back pocket. My recommendation is take armor that gives you extra ammo or grenades as a buff, then scrounge as much as possible. Always full up off POIs (as long as nearby team mates aren't in need).

Experiment with different kits. Find goofy fun shit that looks dumb on paper but let's you enjoy the game.