Flew on Jazeera DXB-KWI once. Liked the product.
A couple of issues:
1. Flew SQ SIN-DXB and wanted to get the BP airside at transit check in at DXB - the handling agent claimed I did not qualify for VOA in Kuwait (so had to enter UAE and go to the check-in desk - no issue there or in Kuwait...)
2. No interline for bags on Jazeera (or at least that was the case 2-3 years ago) - SQ tagged my bag to Jazeera, which resulted in confusion at the gate (the bag flew DXB-KWI on Jazeera the following day)
Technically I can't see an issue with the plan - plenty of passengers connect at KWI.
Then again, I wouldn't be 100% keen on the plan on separate tickets if I was unable to enter Kuwait if needed.