Best way to connect PCB to enclosed AC/DC power supply
When you have a heavy assembly like the PSU you propose, there is an important consideration with wire connections: vibration. The wire harness to the PSU provides isolation between and the rest of your system so that they don't couple.
Your spade-lug proposal defeats that purpose as it makes a direct mechanical connection between the two. Shock and vibe testing will lead to broken terminals and cracked PCBs. You don't want that.
Instead, I would look at a couple of options:

Use wire-to-board connections (e.g, Molex Mini-Fit or similar) between the PSU and your system
Use the crimped spade-lug approach, and outsource the harness-building

The latter approach takes advantage of the equipment the outsource vendor will have on hand, which will not only reduce labor cost but improve repeatability (always an issue with crimp terminals.)