Few questions about your space ship

I just got this game recently and since my usual play style is minimalist and I really dislike clutter, I don't really want to build a fleet and would like to just stick with a single ship.

So with that in mind.

-Can you just upgrade your starting ship or do you have to find or buy better ones? Like say transfer parts from other ships to it, construct them or buy them.

-If you can't, can you reassign your home ship and just sell all the leftovers? I tried to sell the Frontier right after landing but couldn't since it said it was my home ship.

-Are there any shortcuts to their design since placing all the outer doodads and thingamajigs manually isn't really my cup of tea. I'd much rather have a good looking, maxed out prebuilt one than do the aesthetics myself.