You're over thinking it and it appears you're going to end up wasting money on a full sequential ECU like a Haltech, Link, Vipec, etc.
There's no need.. for what you're achieving a Toshi remap would be more than enough, get him to burn you an off the shelf ROM and socket your ECU - pop it in and happy days.
Considering you're using stock injectors, stock afm, etc.. that would be more than sufficient - ram down 1 bar worth of boost and you'll probably make about 220kW
Also FWIW... I'm running a No Frills Adaptronic ECU tuned by myself (only has 4 channels) and it batch fire, batch injector in pairs.
With my self tune running a SS2 Hypergear turbo I can get around 400km+ per tank on 98 OR 540km (best ever) highway driving.
At the moment, I'm running E85 and getting close to 350km per tank (normal civilised driving)..