If I use Quick Ball and the very first card revealed is a Pokemon, do I still have to shuffle my deck?
Yes, you must shuffle your deck regardless of how many cards were revealed for Quick Ball.
Source: PUI Rules Team (2007-10-25), TPCi Rules Team (2012-09-013)

Relevant cards

Note: All applicable cards may not be listed below.
DP2_114
DP5_86
TK3-Lucario_10