I grow under 200W and all my ladies are under 100% light for their entire lives... from the day they pop up out of the soil to the day they're chopped... So 150W is fine... and continuing to veg is only dependent on the hours of light they get - if you keep them under lights for at least 18 hours a day, you can probably veg them until the cows come home! LOL!
But the issue of growth not being as vigorous is, I think, a result of your PPM.. this needs to be a higher at this point... right after cloning, you need a ppm of 500-600, vegging requires between 800-900ppm and when they go into flower, you want that to increase to 1000-1100 (some take it even higher but...) I think you'll see them do really well when you make that adjustment!
Good luck!