Trying to determine ways to compare Olympus to Sony E-Mount to Canon APS-C

I am a professional portrait/figure painter and use photography as a backup to my art work.  I need high quality photos so I have been comparing Olympus OMD EM5 with  Olympus 75mm f1.8, Canon 70D with 70-200 f4 IS and Sony a6000 with Sony 70-200 f4 OSS.  I am finding interesting things but am a long way from final determination as to what to do.  I want to pair down to no more than two systems.

Was hoping Sony would be able to replace Canon but Sony lenses (particularly the 70-200 f4 versions) are not up to the quality of my Canon lenses.  Something interesting I am finding is that I am able to get sharper images from my Olympus 75mm than the other two as well as getting better color than I expected.  Note, all this is preliminary.  I am always amazed at the quality of the Oly 75mm.  I haven't purchased the Olympus 40-150 f2.8 PRO yet.  Would like to compare that Oly lens to Canon and Sony so I would be able to compare equal types of lenses.  It isn't completely fair to compare the Oly 75mm to Canon and Sony 70-200's (not fair to Canon and Sony that is :)).  Still trying to decide if Olympus can replace Canon or Sony since want to sell one of those two systems.

I can't post images I am taking since we have contract agreements with the models where photos are strictly used for painting/drawing references and cannot be exhibited in any other way.  I am open to suggestions as to how to compare for my work.