build camera is a good idea. for the rest i mainly use sktoolbox (https://www.nexusmods.com/valheim/mods/8)
useful commands for building from sktoolbox :
/nocost allows to craft and build everything without needing ressources
/infstam infinite stamina
/fly
/env allows you to set the weather
/tod allows you to control the daylight cycle
/god invulnerability
/revealmap shows the entire map. very useful if you are looking for the perfect spot

if you want to keep your builds compatible with vanilla clients but also build freely without worrying about build height spawn highstones or similar prefabs as foundation when needed
otherwise you can also use /nosup to disable the building support requirements

2 more useful mods that dont break compatibility with the vanilla game:
Repetitive parts -> BuildShare (https://www.nexusmods.com/valheim/mods/5)
if you are working on big projects with repetitive parts you can misuse sth like BuildShare to load, save, copy and paste parts or entire sections of your structures and preview changes which can be a huge time saver

Want to plant bushes, mushrooms ? -> Plant everything (https://www.nexusmods.com/valheim/mods/1042)