I run my sodas around 20 psi for carbing and serving, and I use the standard five or six foot bev hose and one of my old beer faucets.
I don't switch back and forth with soda and beer just to keep it separate. But if you think about it, all the kegs started with soda... so it can be done quite successfully if you have the need.
When you upgrade your faucets (and you will), using the old one for dedicated soda is as good of a use as I can think of.
My next soda is going to be a ginger ale with soem sort of butterscotch flavoring. I haven't worked out what the butterscothc is going to be yet. I will be attempting to make a *Butterbeer*, thank you Harry Potter.
I don't have any problem switching between sodas, but rootbeer has the strongest flavor of them. I have one 'rigging' purely for rootbeer and one other for all other soda.
Presently I have a Dreamsicle soda that was an Old Fashioned Orange Soda Extract with 1/2 bag of Gnome clear cream soda made up to 5 gal with cane sugar.
I don't boil anything. Just mix and carbonate.
If you don't have the ability for 2 regulator pressures, just run the soda off of whatever you have your beer at. It will still be ok, just not as fizzy. You may even like it better.
Have fun and definitely experiment!
And, yes, 5 gal is a lot of soda.