I think it's the light height more than the breeder /strain or pheno that's encouraging the stretch. And if I were in your shoes (errr, tent) I wouldn't worry at all about stretch getting you into trouble. For one thing, you could move your fan and carbon filter onto the top of the tent with the help of a 6" elbow duct connector & that would free up another foot inside your tent.
And one of the biggest things I think I have ever done to improve yields was to start LST as soon as a plant stretched to about 12" or more. With a 90 degree bend trained into the plant you can bring a 36" plant back down to 12", and it will only take up 24" of horizontal space inside the tent. I've grown some monsters under my old 250W HID in my 2'X2'X5'3" tent, and have never been in any danger of running out of headroom. This improved my yields by opening up the canopy and encouraging all the side branches to catch up with the main top cola. Plant auxins did the rest - my BubbleGum grow had 30+ top colas and stayed less that 12" above the ebb n' Gro netpot.
If you find yourself in need & you've never done LST, I have some very good how-to photos I can share with you.
You're right about a long time to wait on a seed to germinate; my past auto's have ranged from 1 to 6 days; averaging 4. I did some more seed surgery yesterday, and this morning I made the call - "time of death, April4, 1:33pm". I'm afraid I got a defective batch of seeds; two out of three have failed & I have one left to start today. That's never happened before. If the third is a dud I'm going to write the seed bank and breeder.
The root riot product is great; same as my rapid rooter from General Hydroponics. I started using those in the early 2000's for seed germination and when I was really heavy into clones / SOG. Been very pleased with the results.
The girls are looking good, making me envious that I don't have any pretty new girls to show off!!! If this seed situation doesn't turn around for me I'm going to run for president and start hanging out with porn stars.
Later Friend!!