Well, that light is definitely cheap enough!3 of these lights would work great in a 2x4.
(US Only) ParfactWorks HB1500 Dimmable 150W LED Grow Light
Parfactworks Samsung LM301H full spectrum led quantum grow boards light for plant veg and bloom, 1000w, 2012w led grow light bar for grow tent indoor plant lightingwww.parfactworks.com
That would make a damn good mom light for sure!
After adjusting the heights of the lights in the new 3x3 with just two lights, three lights in that 2X4 tent And the supplemental red is sure a lot of stuff to play with at the top!