Any V twin is going to be well out of the peak torque range at 80 to 85 mph, usually delivered around 3.400 to 3500 rpm.
telling me that i need to look for something in the 1500 cc range but i am not sure if i agree with that. i am still a new rider,
A nomad 1600 will certainly have more punch than your 750, power is controlled by the twist of the wrist and what's between your ears, not necessarily by experience.
2 things, first I question ( and I'm playing the devils advocate here, not a criticism) what a newb would be doing riding around cars at 80 to 85 mph, (and wanting to increase the speed level) secondly, the more experienced you become, the less threatening 4 wheelers will seem. You may be putting yourself into your own situations.
The shadow may certainly be under powered for a man of your size, cruisers regardless of engine size, when compared to sport bikes and sport tourer's are as about as docile as you can get. Rolling on the throttle on a nomad is not like rolling on the throttle of a
The 900 is a bigger engine size , frame size and wheel base than your shadow by far, I'm just not sure whether the "roll on " is going to be what you expect.
Riding is all about focus, defensive skills, pre-emptive vision, owning your own travel lane and riding with authority (not aggressively), showing people you belong there. I see far to many (and this may not be you) newbs (you can pick em a mile off) riding timidly, stiff armed, petrified and over reacting to traffic, to which 4 wheelers take advantage of this situation and put you in situations that you may not be comfortable with.
We have all been there.