if the bike basically fits and you know enough about bikes to know if it basically fits then you can tell what you want to do to modify the fit.
if not, none of us, thousands of miles away, can tell you what might or might not fit.
As far as the tires .... how can we tell what clearance you have? And "700x28" covers a huge number of tires, all of which have vastly different ride characteristics ... and even inflated sizes.
I think you know all this anyway .... you definitely should.
Grats on the new bike. It will be interesting to hear how things go with it. As for all the rest ......
Apparently some Flite 720s were Al with CF probably bonded together. Not heard about any issues but KHS isn't overwhelmingly popular so I could see why i wouldn't hear much.
Those brifters look huge. What series are they? Old 105?