The M365 is fun, easy to ride, and ideal for commutes. The scooter itself is cheap, but the trade-off is that it does require a lot of maintenence. To have the best and safest experience, you really want to put money into upgrades. In my opinion, that's insanely fun. However if you aren't into DIY, I would suggest going with a different scooter.
After after 7 months of regular riding, here's what I recommend doing when you first get your M365.
Tighten the brakes
One of the most important shortcomings is being able to, ya know, stop. From the factory the hardware brake barely works and the reason it's at all effective is mostly the motor brake kicking in.
Tighten the cable. Grab the cable lightly with pliers, release it, and gently sinch up the tension.
Adjust the two screws mounting the whole caliper assembly so the close pad is as close as possible without rubbing.
Undo the tiny screw in the back and bring in the far pad so it's perfect.
You want the pads as close as possible to the rotor (metal disc) without it obstructing the rotation of the wheel too much. The thing is, some rubbing is fine. Between the possibility of being slightly warped and being at an off-angle, I found that tightening even with rubbing was required to get enough brake grip. I also observed that each adjustment in the assembly shifts over time while riding it such that this issue corrects itself.
Prop the scooter up so you can rotate the rear wheel freely, and spin it + squeeze the lever after each adjustment.
Use a flashlight and close one eye to line up the pads.
Keep the tension screws on the actual brake line at their most relaxed point. Start tensioning them over time when you start to feel the pads wearing down.
Oil the stem lock and protect the tail light wire
The stem lock doesn't have any lubrication from the factory. You probably have found getting it unlocked after initial locking requires two hands and a lot of effort.
Open the lock and carefully drop a small amount of oil directly on the hinge axis. I used simple household olive oil as the mechanism just needs some initial persuasion. Move the whole column around to make sure the oil gets worked into the joint. Clean up any excess with some paper.
Also, a known defect is that the wheel can fray the wire coming out of the red tail light on the rear fender. I used a small scrap bracket to protect it, but many are using a 3D printed piece of plastic to do the job.
Strengthen stem lock
Perhaps the most dangerous design flaw is the stem's locking hook. It can crack after lots of opening & closing the scooter, not to mention bumps and rattling from riding. In fact, mine failed at about 650 km and just about sent me tumbling. Seriously, don't wait for it to fail, preemptively replace it.
A Lithuanian modder makes a much thicker improved part that can be found here: Vilda Shop
They are also generally sold on eBay along with the stock version: eBay Search Results
Secondly, the hinge bolt is another known point of failure. The stock bolt isn't the best design as it breaks at the groove in the middle. The best design is one that is a solid, thick bar all the way through.
For more on this and installation help, see Reinforcing the Defective Xiaomi M365 Stem Lock.
The stock M365 is pretty heavily software-limited. The modding community has produced a way to tweak the scooter's firmware to unlock a lot of potential power and acceleration.
Remember that it's still only a scooter and isn't the most stable means of transportation. Be careful. Mod at your own risk.
To make these changes, you'll use an open-source firmware customization tool. It's exposed as a web app at m365.botox.bz. You'll install a patched .apk (on the page), create your .bin file via the tool, and flash it via bluetooth to your scooter.
Some abbreviations to know:
DRV: "Driver" or the main controller. This is what you customize.
BMS: Battery Management System. Manages battery charging & discharging.
BLE: Bluetooth Module or the handlebar controller. Sits behind the power button.
CFW: Custom Firmware
DYoC: Do your own CFW
KERS: Kinetic Energy Recovery System. What puts drag on the motor when not accelerating.
Xiaomi dislikes these mods and is engaged in a game of cat-and-mouse to prevent the usage of custom firmware. Currently, they've locked down DRV versions 1.4.2 and 1.4.1. The DRV firmware is moddable only at 1.4.0 and below.
See My Xiaomi Mijia M365 DYoC Settings for more on this.
Keep the rubber sleeve on the fender hook
The factory throws on the rubber sleeve without any binding agent. If you have some spray adhesive or superglue, put a drop/tiny spray of it on the hook. Slip the sleeve back on and evenly distribute by pressing it around.
Buy spare tubes
Your first flat won't be fun. You should have a patch kit and try patching first. But it still doesn't hurt to have a set of spares. Don't want to be waiting to get back on the road.
Note you need one front, one back - Xiaomi Mijia M365 Electric Scooter Tires
Cool mods to consider
Russian modders have developed two awesome displays that show you speed, battery level, and other metrics. One requires soldering and mounts on the handlebar, and the other doesn't require soldering and mounts above the power/battery display in the center of the handlebars.
Info is on their Telegram group: Display for Xiaomi Mijia m365
Order form: Order form
Method to add blinkers, a horn, or any other 12V components: Grip Buttons, Blinkers, and Horn
Bag hook - Cheap and adds a lot to the utility of the scooter. There is a common popular model but I don't recommend it because it only mounts via one bolt and doesn't stay put. Look instead for a two-hole design. For example, this model is much more secure.
Carrying bag - Also pretty cheap and allows you to more easily take the scooter inside. Aliexpress
Sandpaper footboard - Several options on Aliexpress
Great source for replacement parts or minor upgrades - Vilda Shop