new engine build need so thoughts!

While I'm not a professional, your build list looks pretty well thought out to me.
I assume the ported cylinder is designed to work with the reed setup since it's also arrow?
Be aware reeds will give very little gain in actual power unless the porting is done to maximize the benefits.
You will also have some tuning to do to get the pipe where you like it. Use the length of tubing between the exhaust port and the start of the cone to move the powerband where you need it. Longer headtube usually moves the power lower in the rpm band while a short headtube usually favors high-end power. You might also find a fatter cone will help if your cylinder breathes really well. I love the KX60 pipe myself for a really good small cc two stroke. The extra volume helps give it a snappy feel and the hit is nice and easy to tune. Takes some custom fabrication to get it nicely packaged on a bicycle though.

everyone ports motors bad and blame it on the cylinder. sheep

im still testing but im using an internal reed with over 200mm of area good enough for a 18mm carb and a true trail ported cylinder and piston. offroad is king. ice racing etc.

anything you have purchased so far is gp styled and nutless besides the pipe and massive carb.then when you complain they say " should spend 300 on a shift kit".

Get the Arrow reed for a Mikuni VM18 carb!

correction a 500 dollar engine thats worth 120 bucks w a 20 dollar external reed is what your pointing at venice. no carb and is not optimum. 600-1000 dollars later it would be ok for flat road more money than brains....