I wouldn't be too concerned about those things, Knox. The black oil is caused by normal cylinder/ring wear (blowby) and is common on engines well into their overhaul lives. Check the engine logbook for confirmation. All Cessnas piston aircraft have a lot of lateral movement in the flap rollers/guides; I've never seen a tight system. Regarding the 110 degree control wheel movement, I wouldn't say that was uncommon. If you've still got doubts, report these things to your A&P on the next 50hr but I've seen similar in many years of working on aircraft.
Steve.