How low can you go?

One of the things I've noticed about my bidding is that I'm more solid than most of my peers when it comes to 2-level overcalls. One of the most annoying overcalls to deal with is 2C over 1D because it's hard to sort out major suit fits. A common continuation is a negative double (only promising one major), and a club raise, and now a minimal opener with only one major doesn't know whether to compete. So I've been trying to be more aggressive in that specific auction.

I held this at matchpoints in fourth seat with two passes and a 1D opening to me:
S A53
H J104
D J7
C QJ983

I'd like to hear opinions on whether this is an appropriate overcall. I did at the table and we had this full auction:

(P) P (1D) 2C;
(X) P (2D) P;
(3NT) AP

And now we get a defensive problem. Partner led the SK, and this hand came down in dummy:
S 1062
H A
D AKQ63
C 10742

What do you play to trick 1?

I lazily played an encouraging spade (low for us), so partner would continue the suit and we could run it. Partner switched, and they wrapped it up. Originally I was annoyed, but I realized I should have done better. Although you don't normally unblock with Axx, I can tell it's safe to do so here. I know partner has at least KQJx because the 10 is in dummy (ruling out KQ10x) and she led the suit when I bid something else (ruling out a lead from shortness). Thus we have the first 4+ spade tricks as long as we cash them.

Partner actually holding KQJ74 switched at trick two thinking I had a stiff and the negative doubler had four. It's probably right from her side to continue anyway to be sure, but I shouldn't have given her a chance to go wrong.