If you like the plane and want to spend your time on it, it's worth fixing.

For me it all depends upon how much the "fix" is worth.

Instead of building the horz stab, I'd be looking for a replacement as a part from the manufacturer.

If this part is reasonably priced, then the likelyhood of fixing the plane increases.

Call it 12.00 for a new Horz. stab that will save you a bunch of work and the effort of building a new one.

You would have to cut the existing one down to the fuselage, and then figure out how to epoxy a new one (you would have to cut it...) in place.

The Firewall is relatively easy. Nothing that a little angled balsa stock can't fix, and a lot of epoxy.

So if the plane cost me say, under 50.00 to fix, it is certainly worth it to me.

If it's more than that, consider that you can take all the hardware and install it into a new(er) maybe better plane.