Is this variant of any interest? how can I improove it?

The idea is to checkmate the king by converting pawns, however, it's mostly a recipe for stalemate, since it's too hard a goal.

This other however is a much simpler an easier proposal:

you can only checkmate by positioning an unatacked night on d1, f1, d8, f8

I also had more fun playing it, but once you and the opponent realize that pawns are key the game is not as fun.

A more complex and elaborate setup where poawns are not as interesting id this final one:

Pieces on the sides prevents lame checkmates from RN combination pieces, however those Dababas are very nasty on knights. I personally don like a lot games with so many pieces.

The only limitation I found is that castle must be done only against rooks, where a chancellor in place may be more useful.

If you weren't gonna give any feedback then simply don't post instead of adding nothing... this is not the first time you have done this either.

What I could propose is adding more knight pieces or fairies into this position to make it easier to target the king, maybe adding 5-check, Stalemate Loses, something along those lines so that endgames are possible to win by having the proper material advantage.

The second design looks like a better start, in my opinion.

The first picture is much like normal chess but with passing allowed, as you can just move the king. If you were to take the setup in the second picture and add a second square for the king it is much the same but checkmating is a lot easier than in the first picture, possibly with stalemate loses rule added. As it stands the second picture is really only adding an extra royal that needs to be taken and of course allows stalemates more easily, with the extra square you get more of the desired effect of the first picture. The third one is similar to a position I have where bots have the outside pieces though you must be cognizant of how much influence they have on the board.

I second the suggestion to add more fairy pieces, and stalemate rules. otherwise the opponent could sacrifice all his pieces to eliminate just the knights leading to a forced draw. another idea is to make several openings between the inner and outer boards. 

What's your trouble?