Posted this a few times before but as others have collectively stated above, the factors that influence bloodtrails are:
In order of importance,
1) Shot placement
2) Attaining at least a partial pass-through
3) broadhead sharpness
4) broadhead size/blade count
Start with the head that you get your best groups with (#1). Choose a shaft that when paired with your broadhead of choice results in a total arrow weight of 10-12 grains per pound of draw weight (#2). Then make sure the broadhead is extremely sharp (#3).
If you make sure that the above bases are covered, bloodtrails won't be an issue and #4 becomes far less significant.
Ron