There is no generally agreed "best" frame, for the same reason there's no generally agreed best band, beer, pizza, clothes brand or whatever - too much personal opinions, not enough measured/measurable data.
If you want to get a clone of your favourite steel frame, then you'd need the ANGLES to be the same as well. But I suppose if ALL the separate frame parts are the same, the angles would pretty much have to work out to be darn close to the same too.
And yeah, frames are measured for fit the same way regardless of material, so it's still your best bet for comparison.
Although you might want to do a net search for "stack and reach" (or something like that), it's another take on how to discuss geometries and bike fit that is gaining popularity.
A farily big thing is design styles. Vintage steel tends to have horizontal and generally higher top tubes, modern designs tend to favor sloping, lower tubes and more exposed seat post. This may make comparisons tricky. Stem design (quill vs threadless) also influences frame layout.
And don't be too concerned with what someone else rides. The fit charts will give you a place to start, that's all. And while it's unlikely to be hopelessy wrong, it's equally unlikely to be the "perfect" fit for you. If you have enough miles to be able to say "this is what works for me" then that trumps chart recommendations any day.
Either way, as you get some more miles under your belt, you may want to tweak the fit anyhow.
How much were you hoping to gain by your "really fast carbon fibre wheels"? Aerodynamic advantages don't really come into play before you start pushing 40 km/h (25 MPH) If you're not there yet, work on the engine, not the vehicle.
Likewise the frame. An aluminium frame is likely (but don't have to be) stiffer than a vintage steel. Ths may well make it feel a lot snappier at takeoff, but whether it'll actually make you faster or not is another issue entirely. Length of ride and fatigue may well play in too.
But yeah, a nice bike is always a nice bike...
Keep in mind that unless you already have a big pile of parts, or is really good at scoring killer deals, assembling a bike part-by-part is likely to be quite a lot more expensive than buying a complete bike.
For my last MTB build, the only things bought at full price were the hubs, everything else was atleast a 30% discount, or came out of my pile. And I think I just about broke even on that one.
