Originally Posted by
Axiom
I'd go with a full Tiagra gruppo (you can also use ultegra chains) than mixed 105/Tiagra etc. I would also prefer a 11-28 cassette and a Red Bont R2 25c tires as an upgrade. A white bont paradigm race saddle would be nice too.
Actually I really like your upgrades. Just complete the tiagra 11-28 groupset and it'll be perfect.