AG & for starting 5 seeds and taking them to 2-3 weeks

My only grow room is by necessity a flowering room, and that is limiting. But I'm thinking of buying an AG7 for a kitchen cupboard to start seeds and veg them to at least 2 weeks, 3 would be better - then move them to DWC/HPS flowering room. I have a few Qs for y'all:

What settings on the unit are best?

I plan to light 24/7 - yes?

I'll take the plants in their AG plugs, and move them to 3 5/8 netcups in hydroton. See any problems with that? I'm concerned that if I veg them as long as I'd like to (say 3 weeks) 5 will be crowding each other up top, and roots may be developed enough that moving them over would be hard. But..... this is a close as I can come to a veg room.

Any other advice appreciated!

I use a modified AG Extra from seed-harvest, using 12/12 from seed. I think it would be difficult with the rapid root production in an AG to get them out after 2-3 weeks without damaging the roots. I may be wrong though.