I doubt we see season three before early-mid 2020. Picard will be at the tail end of 2019/early 2020.
I think ITDUDE means Novemberish for season 2's DVD/Blu-ray release. Which I'm inclined to agree with, get it out for Christmas sales. I agree with you that season 3 likely won't air before spring 2020. My current theory, based on season 2 beginning filming April 2018 and premiering January 2019 and that season 3 begins filming July 2019, we can probably expect a premiere around April/May 2020.
in response to a question about whether there will be a “giant” soundtrack release, jeff russo tweeted back “yes”. previously when asked about the soundtrack album he said he was working on it.
They should include the Discovery Short Treks on the second season Blu-ray, instead of releasing it separately.
On the topic of merch, I ’m hoping for some Discovery pop vinyls to come our way soon I’d love Saru, Georgiou and Pike to add to my collection I’d love to see a Detmer, Airiam, Reno and Tilly to add as well, but I don’t think (besides Tilly) them ever releasing those