I completely agree that pistol runs are somewhat luck-based as far as equipment goes. You can only get so far with two standard pistols, and I remember playing an Ao100 run during which I had to stay with a high power standard pistol well until the seventies, and never met any single exotic/unique pistol throughout the entire game.
Speaking of high-power pistols - IMHO, two high-power pistols would serve your build better on this run than two T-modded ones. You would get 4 extra damage per dualshot on average, and you would also gain a 1/12 chance per shot for knockback. You would need to reload more often, sure - but with these guns you would still have a good chance of killing a single opponent before you need to reload.
You are also right about SoG3 - the DPS increase between SoG2 and SoG3 is ~75%. IMHO, picking up SoG3 immediately after Gun Kata (and leaving Finesse and Whizkid for one level later) might serve you well. In fact, you may consider going for SoG3 even before or right after Dualgunner. Then again, on HNTR you might not gain enough experience to reach WK with such delaying.
Since you are a Scout, use your speed. Barons, for example, have 100% speed, and as such are actually slower than you are. With MGK, you can easily squeeze either a dualshot or a move between any of its actions without a chance to retaliate - so simply try to dodge until it moves or fires, then fire and dodge again until it moves or fires again. Aside from reloading and fighting in corridors, you should be quite safe.
Similar tactics would work against a mancubus, but this case you don't want it to fire at all. But - mancubi are really sluggish (80% speed). You can best deal with them at the edge of LOS - with MGK you can dualfire twice and then move out of its LOS. It should follow you immediately, so just dualfire twice again and move out. Rinse and repeat. If you need to reload, move out of its LOS first.
Revenants are _the_ bane of pistol runs. 50% bullet resistance with 2 armor on top make you really feel like pea-shooting. Those energy pistols you wanted to assemble would help immensely. Otherwise, with MGK you are still faster then revenants, so you cas use the same strategy as against mancubi - only with a single dualshot between moves, and never ever use the Wait command while standing against them.
Also, consider switching to running tactics when needed, especially before you acquire Dodgemaster. Your accuracy will take hit, but enemies' accuracy will take an even harder hit, and it allows for quicker repositioning, for examplne when you need to reload.
I hope we will see a YAVP post from you soon enough :).