My MiniX U9-H working quite ok.

Just "sometimes" it force close for no blerdy reason. A quick reopen then it's fine again.

I blame Astro app dev being nonsense LOL.

Minix Neo U1, latest app version works.. See thread title..
Don't know of any free one.. Another paid? yes.. Discussed one recently.. Ships with Minix boxes. You are better off with a paid one. Just a few RM and yours for life, updates included.

Sorry, can't confirm that. Last gamepad I used was the PS3 Dualshock controller on my previous Minix Neo X8-H Plus and it worked wired and wireless. Unfortunately, same can't be said for using it on the Minix Neo U1 as Lollipop removed its drivers or something. Well, at Rm1xx, not so expensive la for peace of mind. Sure, you can go ahead and buy the Ipega, see if it works. Thing is, there are several ipega versions.. So good luck..    Do report back, if it works and how well.
It could be an issue with your network as the Mibox 3S doesn't have an Ethernet port for wired connections. WiFi network has to be healthy. However, once you've determined it's not from your network, then it has to be from the servers. As for VPN? For English content & within Malaysia (for now)? No VPN needed.. Can't speak for Chinese or otherwise content as some require a VPN connection to access.
Good... I don't have a As*** subscription, so can only test with free content. For over various app updates, it has always worked. Tested last night and was able to play two episodes of Oh My English!, smooth from launch till end.

Edit: Should you feel like temporarily sharing your subscription login details or for a longer test, let me know.. I could do that.. before you purchase the box.

use your stock unifi white stb box and sideload the astro on the go apps...

just not sure how the latest update will work or not on the unifi stb