Ships in Starmade are like taste in music. There are all kinds of different tastes, yet none are wrong or 'suck' as you say.
If your ships theme is industrial, then maybe a blocky form with more exposed systems will work much better than a ship with a theme of, medical per se.
Colours you'll just have to experiment with.
With armour and armament, some configurations are better than others, and other configurations on other ships are better then others. For eg. a "standard" (usually a small) roleplay science cruiser isnt going to necessarily go well with a planet buster weapon system, due to power drain and size, whereas small weapons and defence turrets will (unless the lore for your ship says the race that built the ships is technologically superior).
In a ship built for combat, with shields you can decide what type of hull you want to use without sacrificing your ship, without shields you would want the best type of armour with a thick shell with bulkheads probably for best chances at surviving. You would also want a power system that produces power whilst moving and firing multiple weapons and turrets.
You yourself as the builder have your own opinion whether your ship is 'good', 'meh' or 'shit'. If you think you've made a good frame, hull, start, save a blueprint and keep expanding on it.
Reviews can be genuine thoughts by the downloader and their own opinions, or trolls just trying to ruin peoples days.
People do post 'bad' ships on the dock, sometimes on purpose, sometimes for fun. Reviews just 'help' thin the heard of ones that are bad jokes and ones that deserve recognition. I've looked through your community postings, your ships do look genuinely great, but aesthetics and purpose are 2 different things.
Hope this helps. Hope i havn't droned on too long and gotten off topic too much. I tend to do that.
_Scooter98_