I would advise you to wait to put in LMB at least till the fall. I have seen many people put in everything at once, and have alot of problems with the bass eating all the minnows from the start. Once you bass start that, then you are just buying expensive bass food. The minnows will have a hard time getting started after that. I have delivered minnows to ponds with bass in them and you could see the bass just eating them up almost as fast as they come off the truck. The bad thing about waiting is just the wait.
Grass carp are very good at what they do while small, but the bigger they get, the less veggies they eat. They seem to like to eat fish food more the older they get. Only get some if you need them. You could put some in now, but by the time the green stuff grows, they may be too big and don't want to eat it.
Enjoy your pond.
Kodiak