I cannot say much about the Trimaran, other than that it looks like one, but on your frigate-like creation (since it has all the sails):
It's nice you put effort in making the underwater part of the hull, yet it goes at a 45 degree angle in your case, while it should curve. Also, the hull would be rather "fat" for the lack of a better word, and curve more elegant at the stern.
The bow would also curve, and that much steeper so that it's almost at 90 degrees above the waterline (sometimes it would curve back due to the tumblehome). In addition to that the hull would curve in two ways (width and height) and also have said tumblehome! I also get the impression your masts and yards are way too thick, at least the upper parts should be thinner.
The stern is looking quite good, but it should, be angular if you want it to be realistic. I get the impression, it's more difficult to build with LDD than with real bricks, but there have been some very good LDD MOCs.
So, I guess you wanted feedback, so here it is!
I hope you're successful in improving your creations, they are not bad, but there's a lot to be improved nonetheless.