Okay, I'll answer your posts in order
Post 1: Why do you have the t8's on in the morning at all? it makes more sense to me to just have all the lighting be at the same time, or do a siesta period where its like 4 hours of whatever lighting on, hour or two no light, 4 hours of that same whatever lighting on, then night time. The fish won't care how much light they do or don't have most of the day, its your plants that would care more. If you want, start at 6 hours for now, you can eventually work your way up to 8 hours...maybe even 10 but I think 10 might be pushing it? But its possible and do-able for sure.
Post 2: I don't have a calculator mostly because I'm lazy and don't use one...but I'm sure you can find one on either The Planted Tank, Aquatic Plant Central, or The Barr Report. Personally, I just EI dose or do a generalized PPS-Pro thing, which are both pre-measured and pre-set up amounts. I do tweak my EI dosing when needed though, which I'm feeling I might have to do again soon. My non-EI dosed tanks aren't EI dosed because I don't want to do weekly water changes on them, and because they are dirtied tanks and get a buttload of nutrients for the substrate itself (although still not enough hence why I do the PPS-Pro to supplement that...although I need to get more strict about it).
Post 3: That sounds like a good starting point, seems very similar in nature to the PPS-Pro thing I'm doing for my 10 and 5.5 gallon. Personally, I buy my ferts from Nilcog, who has profiles on multiple planted aquarium websites, as his prices are good and he is helpful with questions. The PPS-Pro thing I'm using is a liquid mix he sells where its just put in however many ml of macro and micro per gallon daily, which is what it seems like what you linked to is saying. PPS-Pro is nice but the only thing that sucks about it is you are providing what the plants need for a day, giving you less leeway when you skip a day and lessening growth, which isn't always a bad thing since trimming a large tank can get annoying real fast.
