A Modest Proposal:

Get on Facebook or Craigslist and buy an unloved, higher quality road or MTB from the late '80s/early '90s - very solid bikes. Instead of screwing up your finicky modern bike or trying to perfect something junky, get something of very solid quality that will definitely "tune up" to a very high degree. Spend like $100-200. Try to get it working like new. Look for Deore, XC, 105, RX100, GPX, Cyclone, EX, GPX, etc.