Hey mate. Very very good job! The bike looks great. But are you going to put the side covers back on? I notice you've left the tabs on the frame and tank. At the moment it looks a little cluttered under there with the battery box sitting out in the open.
I've done one up as a cafe racer myself and keep in mind that since these are kick start (unless you have the very rare CB250RS-D) you can get away with a very very small battery (or no battery at all if you choose). I'm using a 1.2ma one from SuperCheap which cost $30 and it's been working a treat for a year now. Very easy to hide as well.
Also if you decide the upgrade the carby, these run very well on both a VM32 or TM33. I have the TM33 on mine and it really turns it into a weapon. I've topped it out at 155km/h on the flat indicated by GPS, although I also have a high compression piston.
I'll be following this build! These bikes are legendary.