Phantom, looks good, time now to get it out there. If u ever need a new one, have a look at the Trojan. I found my offcut in a scrap bin - as I said, much too longa blade. Material/blade was about 1.7mm thick.
Have a look at a Trojan Trenching Shovel with 'D' fibreglass handle.
After I had a few cheapies break at the same point urs did above, I bit the bullet and tried this decent one - a long handled one (the ruler shown is a 60cm one).
The blade is wayyy too long. From mem I cut off about 4-5...
Disclaimer; my knowledge is based on personal research when we upgraded to lithium 3 months ago. We tripled usable battery capacity and tripled solar input for a 25kg net gain.
There won't be any longevity advantage unless u set it up right, as mentioned by others above.
First thing u should do...