I may not have the answer you want to hear, but I'm familiar enough with well systems to try and help.
(Just to qualify what I'm about to say/ask in this thread, part of what I do to put food on the table is perform the well technical capacity calc portion of TMF's, and distribution design, for public non-community transient and non-transient well water systems. I'm the engineer-type that puts together the 2-part well pump test requirements, for the drillers out there that are familiar with NJ.)
Is it an exposed well head, or a buried well head, also can you explain your "well house". How big, slab, no slab, heated, construction, etc. Also, why does it come up to a pump house, and not run underground directly to the structure? Is it the underground section that is freezing, and if so, how far below the surface is the line running from the well house to the structure? When it gets to the structure, does it enter into a conditioned space or unconditioned space? Where is the line heat traced, and is there insulation on the line as well? Am I right in reading you: your pump is in the ground, pressure line comes up into some sort of pump house, then dives back in the ground and over to your slab/foundation?
I can't ever remember running across a commercial site that had its well line freeze up, but then everything we deal with is run underground or through conditioned spaces. Also, regardless if you have the pump in the ground or in your mud room, if the line itself is exposed, it's going to freeze unless freeze protection is properly addressed. You can run outdoor water lines 30 feet over head in pipe racks exposed to the weather that traverse a thousand feet, and as long as you have the correct freeze protection and it's installed and insulated properly, it won't freeze.
I think the quick-hit, low hanging fruit option here is to take a hard look at your existing freeze protection scheme, and try to address that before changing the system. It could be as simple as not having the tracing properly affixed to the pipe, or gaps in the insulation.
Can you take a picture of the area that is freezing?