The HLG 100's are nice lights. They have a wider spread than the 135's, but the 135's are dimmable. I have both, and both are great. Too bad the 135 V1's are gone cause those were even cheaper than a 100 before they sold out. But if you wanted to add another light in there right now I would recommend the 135 Rspec.
Ultra High Efficiency LED Boards for DIY. QB288 has 288pcs Samsung LM301H LED. 135 Watt Lamp Kit.
horticulturelightinggroup.com
I personally think you should just use what you have for now, and add more later, but us stoners have a hard time waiting sometimes, lol. If you do get bit buy the grow light bug, use coupon code "RIU10" for 10% off.
Here's a few quick pics I just took of my veg tent with the 100's. 2x4 tent, 2 100's in 3000k. They're about 20-24" above the plants right now. A free lux app downloaded on a cell phone can give you somewhat of an idea of the intensity of the light also.
I know the Chem 91's on the left don't look super happy, but it's a new strain to me, and it's a lot more demanding and picky plant than most, lol.
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Hope this helps give you an idea.