Filtering

Hi. New to the forum so please be patient while I figure out how this works.
I have recently started to filter my beer. From secondary through steelhead pump into home filter system and then into keg.After making an 11 gal. batch I used a 13 gal. jar for secondary and top racked 5 gal. into the first keg , then pumped the second 5 gal. through a 5 micron filter. This pale ale is now at 36 degrees, carbonated at 2.4 vol.c02. and I cannot tell any difference in side by side test for taste , color , or aroma. Both kegs seem identical. Should I have used a finer filter? Should I have pushed the beer "more slowly " through the filter.Will the action of the pump infuse oxygen into the beer? Better to use kegs to push with c02 through filter?
Lots of questions--new to filtering.

With my setup I use two filter housings one with a 5 micron pre-filter (prevent clogging) and the other with a 1 micron, connected in series.  In my opinion transfer from keg to keg using CO2 is easier. My reason for filtering was to get most of the yeast out of the keg as you waste the first couple of yeast ridden pints during dispensing. As I've read you need a 1 micron filter to filter out yeast.