Vader 150

[ProDigit]

Greetings all!
I just purchased a Vader 150 *edit: X-Pro 150 from Walmart* that was on sale.
I always wanted to have a grom, but couldn't justify the 133-200% ask price on second hand sites.

I realize that buying a new Vader (X-Pro) with mods, I will come close to that price anyway.

Mine is a 150cc and it's currently in the process of being shipped to me.
I went with the slightly more expensive 150cc, seeing that I'll be using it on rural roads up to 55mph.
I just wanted something with excellent gas mileage, and the thing keeping these bikes from getting even better gas mileage is the gearing.

So my first mod will be, to swap the 14/15 (stock)t front sprocket to a 17T, which will lower torque. I don't want to have a sluggish bike for around town, hence the 150cc.

My second mod would be to reduce the rear sprocket size to as small as allowed. The 34t rear, I'll probably want to swap for a 32 or 30 if it would fit. My current option is rebelgears, which makes hardened aluminum sprockets, and I have had success with a 28T sprocket on another bike for well over 5K miles before selling. The sprocket had minimal wear.
I will want to buy a cheaper, steel sprocket, but don't know where to find a cheap rear sprocket replacement?
My aim with swapping out the front and rear sprockets, is to make 4th gear like stock 5th, allowing me to have a good overdrive gear for when cruising downtown (at 35-55mph), which should increase mpg by about 30% over stock.

3rd mod would be an oil drain bolt replacement to a small valve, or some other solution to draining the oil without needing to take off the exhaust. Any ideas?

4th, I will need to find grade 10 or grade 8 motor mount bolts. I don't know if the 150 uses the same bolts as the 125?

5th, I bought handlebar risers. Slightly cheaper than swapping out the handlebars. All I want is the handlebars to be closer to my body (about 4 to 5 inches up and back), because I'm a tall person.

6th, I will spray paint, and coat the frame with black plastidip, as it's very successful at sniffing out rust and covering it up. We have a plastidip painted steel bench in our yard that hasn't leaked one bit of rust in over 7 years, and looks better than some people's stock bench of 3 months.
The exhaust and engine parts that need corrosion protection, I might spray paint them with high heat thermal spray paint.

I wished I had the skills to weld a third motor mount, but I don't.

7th, I have a lithium 12V battery, I will want to replace the stock battery with.

Lastly, I want to do as little work on it as possible. I'll try to keep the bike under a tent or shaded area, to protect it from the elements, and instead of a better carburetor, I can just play with the choke. My other Chinese 125cc bike has the same issue, where the choke would increase fuel ratio, and where I could feel the bike's performance increase as I dialed in just a tad of choke.

The benefit of this is, that I can run it very lean if I want to (like at slower, non-highway speeds) without any modifications.

My last question is,where does the bike fail most electricall on the harness? I might want to put some extra coating or protection on that area.

Anything else that's highly recommended?