First off, I must say that I really do like the craftsmanship in this build. For asthetics, it's a great job. Unfortunately, It's a stupid idea. If a friend of mine came up to me and started talking about a t5/led hybrid I would laugh thinking it were a joke. T5 and LED together is no more "hybrid" than a dog and tapeworms.
I am interested in knowing what reasons you had for thinking this was a good idea though. I understand that there are MH/T5 combos but the whole point to that is to increase the light output above what the MH can put out on it's own as well as add the option to have an actinic lighting cycle. T5 have a broader light spectrum but with LED you can use combos of reds, blues, purples, turquis, cool whites, neutral whites, warm whites, etc to fill in spectrums and bring out all the colors of your tank while setting all the colors and brightness to match your needs.
There may still be some people that argue that LEDs have some disadvantages but it's a moot arguement. A year ago, LEDs were still fairly new and just starting to get a real establishment above a lot of tanks, today LEDs are tried, they are tested, and they are true. LEDs are to lighting what a Vortech is to Powerheads.