Carb spacer seems fine from factory, (bike isn't restricted like some used to be) I ended up running the standard jetting, I tried bigger and smaller and all combinations of needle height with my wideband and standard was as good as it got (I think needle mods would improve it but I haven't been bothered to get into that drama too much yet)

You are probably correct on the intake valve, it was something I was thinking of today.
Same with the plug, I noticed it's facing away from the chamber when I took the head off, new one will be indexed