first off a couple of things. Can you try and do paragraphs, just makes it a LOT easier to read :-)
And you'll find that you need to be using millimetres for all measurements. Inches just confuse matters and most slicers just look at them go: burble burble burble :-)

that file would print as it is - don't see any issues.
You'd need a fairly high resolution, but you've got a nice flat base to start with.
Hell you could always use supports - I pretty much always design a print so that I never use supports, but that takes practice and without a printer. Any designs you make will NOT be optimised for supportless 3d printing.

But as long as you expect to do some post print filing and sanding, it shouldn't be an issue.
Only real issue is length.
If you split it in half lengthwise you'd need to dogleg the cut so you have overlapping section to glue.


Strength on fdm prints is largely dependant on print orientation.

Print that peice flat and pla would be absolutely fine.
But the armadillo would be almost as strong as the carbon fibre one.

Bound to be pu glue/solvent around.
For pla i use uhu all purpose. I get a partial dissolve so very strong bond.