Don't get me wrong here...the chinese motors can be made to be dependable. Generally, the heads are fine...they last a long time without issue. The piston and cylinder, too, quite honestly, are not the issue provided you are not overheating it and keeping the oil changed. The bottom end is where things start falling apart. Transmissions, electronics, clutches, kickers, and crank bearings...those seem to wear out before the top end. Is there something that can be done? Sure...but then you start adding lots of cost. For example, you can (i think) direct swap a TRX90 transmission into a chinese mid-block case or with some minor mods. That solves your transmission issue. Electronics, the ricky stators are $60...that fixes your electronics. Replace the bottom end bearings with high quality japanese bearings, including the crank bearings. The clutch plates are fine, its the basket that seems to have issues. Again, the TRX90 basket can be used, but you need to swap the large gear on it. You'll need to do custom machining and know what you're doing. The parts you cannot solve for are the kickstarter gear and the kick-in gear mesh gear. There is nothing that I'm aware of that resolves this. However, if you do all those other things, you will increase life of the engine significantly.
After you do all of this, you'll have added another 300-400 in cost to the engine...maybe more depending on how much you can do yourself. At that point, you'd be better off buying two chinese engines...and when the first one dies, keep it for parts, and drop a new one in.
The honda Nice is a forever motor. If you don't muck with it too much, it should last you a lifetime with limited issues. Sure, you'll have to bore it over in about 20000-25000 miles. Sure you'll have to replace the clutches. But you shouldn't have to do much more but keep it clean, tuned, and filled with good, fresh oil and clean the spinner after every 2-3k miles.