First composition/ Deduce a mate in 4

PROBLEM: Remove any piece or pawn (just 1) so that the resulting position is a mate in 4 for white.

White to play.

Hey everyone, recently I wanted to try my hand at composing some problems, here is my first attempt that wasn't too bad. Feedback for how I could improve the puzzle is appreciated

Creative effort! It is an unusual stipulation in the sense that #4 usually implies that shorter checkmates count as well. But you clearly meant "exactly 4 moves". If you would want it to mean "no more than 4 moves" then you should change the stipulation to "remove a white unit such that ...".

On content you achieved the removal of the most unlikely unit - and therefore the most likely unit problemwise - which shows you have the right instincts for composing.

Technically, some items call for improvement:

- There is a dual on the 3rd white move; both queen and rook sacrifice work

- All the checks are disturbing. Good problems commonly have at least one quiet move, in particular the key move (1st move).

Thanks! I did see the dual but I didn't mind as much, cause it doesn't lead to a different checkmate/mating square like other duals might. 

I'm not very familiar with the wording of problems so hearing that definitely helps. I'll rewrite the wording.

As for the checks, it's very true, but so far composing a problem that starts with a quiet key move seems a lot harder, and my efforts haven't yielded anything nice in that regard so far, but I'll keep trying

Yes, I know! A series of checks is much easier.

You should get rid of the dual though because it is in the main line of the 4-mover. By problemist standards it's not any better when the checkmate positions are similar. As an example on how to undual such positions, imagine that the white queen would be on a8. Then you would have to sacrifice the rook first as the c6-pawn is in the queens way! Just one of a million tricks problem composers use to tackle such issues. Unfortunately, every trick requires a redesign of the original diagram.