Finished primary on a plum melomel, mind helping me figure out secondary ?

Starting gravity was 1.072, it's now 0.990 after 23 days, with an estimated ABV of 10.8, more than the theoretical alcohol tolerance of the safale S-04 I used. I recon the fermentation is complete, but I guess I can make another gravity reading in a few days to make sure.

It tastes... Not super great now but with potential, there is a strong alcoholic taste that I guess will mellow over time, there is body and a plum aftertaste, as well as some honey-ness left. It's quite acidic and astringent like a red wine.

I'd say it's a semi dry mead, which is fine to me so I'll probably not back sweeten

My question is, with those information and your experience, what would you add to secondary to improve it ? I'd like to balance the acidity. Also, what flavour would you add to a plum mead ?