I would say the Samyang 14mm F2.8, although, as said in my presentation post, the lack of AF is now causing me trouble (kids are not always easy to follow).
So, now, probably the 35mm f1.4, despite its weight.
Thomas
With the immense depth of field your lens should have, I think I would zone focus the lens to about 1 meter then set the lens at f/8 and about 1/100sec, and employ AUTO ISO if necessary. Your hit rate should be pretty high with this setup.
--Ron