1st grow, thoughts please

Just trying to get a feel for how im doing.

Will start with setup,
Cabinet 2x4x4 Mylar lined interior
20x Bright White 23Watt 5000k CFL (Veg)
20x Soft White 23Watt 2700k CFL (On standby for flowering)
Currently a large Hepa fan mounted on top for exhaust (Ordering carbon filter/fan this week)
3x 3inch inlet holes with ultra fine screen to catch bugs and dust and such. Quite a bit of vacuum coming through, holds the front panel to the box with ease.
Fox Farm nutrient trio
Calimagic
Watering and mixing nutes into Ph'd store bought gallons of water (There are extremely mixed opinions on use of tap water, otherwise id use it)
Soil grow, mixed myself.
Humidity has been hard to keep up seems to want to hover at 35-40%

Now i've done tons of reading and have done my best to make sense of it all and put the knowledge to work, so far so good I think. I started with 2 plants, at first one seemed to be slow to grow and a bit of an underdog, however the balance seems to have shifted a bit. The once struggling plant seems to have gone nuts branching and bushing out, while the other only seems to want to grow one tall main area despite repeated tying down to help lower branches to get the light required for proper growth as CFL does not penetrate very well. I followed the same training methods for both plants, pulling them over just a bit to promote branching up. I also topped both plants or my best attempt at it. The one just keeps growing around the bend and striving for upward growth with little to no branching. Both had enormous fan leaves I have since removed due to excess shade, which definitely helped the once runt but not so much for the other.

Few questions
Heat as you may imagine is real with so many bulbs, temps with all running hover between 79-81 degree.
Is this too high? And will the filter/fan help mitigate more or less heat?
With the training of them the one just seems untrainable, is this perhaps just in the genetics of the plant to just wanna grow up with no real branching?
Should I remove top fan leaves to the sides of the topped nodes to be exposed to light better?
Is the high amount of vacuum good or bad?

Any thoughts, suggestions, or any type of critique would be appreciated. Doing my best for first time but am sure a pointer or two could help. Thanks

Pictures please

I would lift them and fill those pots. It would give you a lot more room for roots. I wouldn't remove the fan leaves. Your temps are fine. The fan and filter should help with air flow and the vacuum is fine. I can't tell too much about the shape of your "problem" plant, but I would think you could make a small hole in the edge of the pot (after filling it with soil), insert a string, and tie the tall main over to the side of the pot. You should get a lot of new side shoots growing vertically that way. You may have to start slowly, bending it a little each day while tightening the string I've done it in the past with success. Good luck. It looks like you're off to a great start!

Well im sure I know what you mean just not 100% certain how to execute without damaging them. Can they just be lifted out of pot? Or do i like gently upside down them? Ofc while having ahold of it

Any "damage" you do to the plant will delay its growth. Picking off fan leaves is damage. This is where, as I'm sure you've read, LST (low stress training) comes in. Helping the plant bend certain ways in order for the smaller inner shoots To join
the party. As Cindysid suggested, pots that you can use to anchor twine or wire to keep the branches in place. You could use your pots by making some kind of headband around the pot at the top and using that to affix your ties.

Yea the zip ties you kinda see are headbands and there are posts in them to tie to. Can kinda see a loosely tied rope on the problematic one

You'll need to wait until you repot them. And you will soon. Try to use something with straight sides so the roots have maxeoom to spread.
Bigger roots=Bigger buds.

If they've been in those pots for awhile it should be fairly easy to tip them out. Just gently upend them while holding the stem between your fingers with your hand flat against the top of the soil. They should have a pretty decent root system by the looks of them. They will appreciate the "lift"...lol

Awesome, thanks so much. Will def go square and repot them. No such thing as too soon im assuming?