Should transport ships have more capacity?

Now I'm not saying they need a buff, but every time I use the transport ships they feel so clunky, so I wonder if they could be improved without breaking balance.

Let's say Careening gives +10 instead of +5 capacity, or increase the base capacity from 5 to 10.

An extra +5 capacity sounds like a good quality of life improvement to me, but I'm not that familiar with the meta game so I wonder if that's doable?

Some civs get transport ships with only 10 capacity, which is pretty rough with 200 pop. I have to wonder if the original transport ships were made with 75 pop in mind?