I personally don't like the idea of selling short-term calls against LEAPS. But, I've honestly never tried to buy a warrant and then sell a LEAP. So, I can't say if the idea has merit or not. If you have some specifics, that would help.
Ignoring the math, here's some things I'd question, if I were considering doing that trade:
1- Vega exposure.
2- Warrants are not as standardized as options, so you'd need to know the specifics of that warrant.
3- Is it American or European style for assignment purposes.
4- Is it even available, and if so, how liquid is it.
5- How assignment is handled for warrants, and is a short LEAP call considered covered by a warrant, meaning will the broker see it as a diagonal spread or as a naked call and an unrelated warrant.
Like I say, I don't know anything about trading warrants, but these are things I'd ask. Hopefully, there is someone more knowledgeable on the forum who could chime in. I'd be interested to hear what others think.
Without specific numbers it's hard to say if this would work out better than just doing covered calls. As far as margining covered calls, I prefer to do covered calls and use diagonals for leverage in order to limit risk.