The Angel is from Superchess by Henk van Haeringen, and I love that piece.
Witch + Angel?
gg
If I were black I would certainly not offer a draw here. Up a pawn and a lot of potential pawn breaks left, a lot to play for. If black would have all the time in the world, then one plan would be to play a lot of pawn moves like d5, e5, f4, g5, e4 to gain some space, the guard might want to go on a trip, like Gd6, Gc5, Gb4, The witch might want to just protect the king from back rank mates, i.e. Ki8, Wh8.
Of course white will not just stand still while black execute his plans, but the main point is that there is still a lot to play for, even if there is no direct tactics. As long as black finds a move to make progress,, then no reason to offer a draw. Black can start with Qe5 when Qb2 becomes some sort of a threat and you can always hope white blunders with something like Qa6 Rxg2 forgetting that his guard is pinned.
It is impossible to make deep analysis when both sides have a lot of possible moves, but one possible sequence is 1...Qe5 2.d4 Qa5 3.a4 Qc3 4.Qf2 Gd6 and then it looks like your plan of getting your guard to e4 can be fulfilled (Gd5, Ge4 is a plan).
There are a lot of hypothetical lines, such as if white plays c3 instead of d4, but overall whites pawns on the queenside will be weaker than blacks pawns since black has his guard there. Whites pawn moves near his king makes his guard needed to defend there while blacks king looks safe without any piece really needing to defend. An excellent example of why it can be advantageous to have castled queenside when you get to endgames.
As a side note I would not have accepted a draw as black, even if both sides had the same amount of pawns.
If I would be white against a stronger player, then I would feel lucky if I could hold a draw. I count 5 weak white pawns: a2,c2,d2,e2, g2 and only 2 weak black pawns: a7, c7. Black has a safer king, a more active queen and is up a pawn. This is the sort of position I feel a GM might say white is dead lost, while I think there is a lot to fight for.
No way am I drawing this off as black.
Also, no need for c6 to defend the guard from the queen, just grab the b2 pawn and the queen cannot capture the guard, she is burdened with protecting the rook.
I think it gives black a lot more activity, you're certainly winning if you play Qxb2. After c6, black still clearly has the edge and there's really no way you can lose unless you do something crazy. You gotta have more faith in yourself. If in 10, maybe 20 moves, you still think progress isn't forthcoming, then ok, maybe we can draw it off.
I'm also ready for another weird pieces game, are there more pieces that you wish to explore besides the Witch?