the frame I tried out was definitely the valencia, they had a few iro mark vs in the shop for sale super cheap to clear space. it's not exotic and felt like a pretty typical steel track frame.

I think it's more unique to find nerdy, hard to find, or obscure parts. a basic build is about as interesting as going into a store and buying the fanciest everything they have in my opinion. but i'm kind of weird.

and i think the most important parts in order
1)frame that fits
2)saddle, handlebars, pedals/foot retention, and stem that fits
3)tires
4)hubs, wheels
5)crank + bb, chain, headset

it's not the best way to put it, as with a bike there are so few parts even the "least important" will play a factor in ride, but you can get by just fine with a 20 dollar shimano sealed bb and it won't feel all that different from a 100 dollar sugino 75 bb. that 80 dollar difference would be much better put into clipless shoes or a proper saddle.