With the merge of both the SP and SR1 communities, I believe there will be two separate types of crafts, mission based and creation based. The mission based crafts won’t include any XML modding, and will be used to travel to other planets, and is more focused on the engineering side from SR1.
The creation based side, and most likely the larger side, will contain builds with a XML modded engines and parts such as infinite fuel tanks. They will be more focused on the look of the craft than the functionality. These might merge with the mission side, but will leave out XML mods.
Which one will you be?