For unifi aka hypptv, new astro go and perhaps other future media, you gotta go with atv boxes ie MiBox Mecool Nvidia Shield to name a few

Do you want to go thru hassle to constantly update apk just bcos of incompatibility when the provider change or update at their end?

Latest hypptv app as in the Unifi PlayTV in Play store that has a Fireball Football on its picture?

You have Unifi account? Or intend to create monthly accounts to enjoy free 1 month Premium usage?

Recently, I received a message on the old official Unifi Playtv app on my mobile indicating, my free to use account is eligible to use the latest app (fireball football). I reckon every one should already migrated to new app. The old official app no longer works and would refer to use the new app on my in phone.

I don't use use Unifi PlayTV much in my Tx3mini. It still works with the old modded app. I will be able to offer help if you can furnish me with more information of your needs. Intend to testout the new app.

At the moment, it seems you priority is Unifi PlayTV, YouTube and later venture to Kodi. There are pros and cons of the 3 boxes you mentioned, budget, software, hardware requirements and ease of use.

Lastly, what are the problems you see arising mentioned in your post? Is it related to migration and app usage rather than box compatibility?

Downloaded the latest ver1.3.5 from Playstore within Tx3 mini. And it runs well with my free account with only the few live TV channels. Only small issue of selecting the Favourite channels from Landing page. On handphone portrait, it opens correctly to favourite channels page, on Tx3 mini ( landscape) it opens Profile page instead, and from profile page have to click the Favourite channels there.

Otherwise, no issue with using Unifi Playtv with Tx3 mini with Root Switch Closed. In fact, the app don't need to be modded to use with boxes that has closed root unlike in the old app which has some restrictions requiring mod apk (i.e. WiFi and Root error)

Other boxes which are rooted, will require mod apk downloaded from somewhere and install separately from Playstore. As for Tx3 mini, it is installed directly from Playstore as in my case or other TV box with Android Mobile OS. Not sure if you can find it in MiboxS Android TV OS Playstore.

Latest Mod app available version is only version 1.2.3 from Unifi thread if I am not mistaken. Official Playstore is version 1.3.5.

This app is still very much Mobile OS app requiring Touch screen, but it works flawlessly with a normal mouse with Scoll. The scrolling works well. Using IR remote only with directional pad is not possible, as the app don't recognise the up and down button - it somewhat can register left right ok back, but no indicator where the selection box is on most menu. So even if you intend to use it on MiboxS, mouse or air mouse is required.

The only issue which the app inherited from its predecessor is that the app stops operating when it detects root access during startup. I needed to clear cache, clear app data, close root and login again with username and password.  It's predecessor is more aggressive whereby the app runs in the background and check for root.

I can select the max 1.9Mbps picture quality for live channels which should equate to 720p. However the picture seems pixelated to me even on 42" TV. Don't know if this is the same for other boxes or inherent of the app itself and can't be helped.

As for myself, I watch YouTube most, second is AstroGo and third is a couple of VOD apps.
Smart YouTube TV - Ad free - based on YouTube TV app, suitable with IR remote.
Vanced YouTube - Ad free - mod version of YouTube mobile app - suitable with air mouse.

AstroGo is the mainstay of people using Tx3 mini or other boxes which is not rooted or can be unroot, bar MiboxS which currently has issue with the AstroGo mobile version.

VOD apps - I use Newfast which sadly has closed for new registration. It is really like free Netflix with Chinese subs and interface. Other ones are Stremio for P2P VOD of latest flix and TVZion which has regular auto updates. There are a bunch of other renown VOD apps, each their Pros and cons. BeeTV, Cyberflix and lots more. Asian Drama VOD, are also easily available.

Other free IPTV,  I do keep a few in the TV box, but only if I find it stable, has dedicated MY section after testing them in my spare phone for a while. Some of them has 18+ channels which are not suitable.  Tivimate with manual setting, TeddyTV plus comes to mind. Free IPTV majority originates from Chinese/Taiwan broadcast, so does the free IPTV apps are more Chinese oriented and don't expect subtitles to be in Malay. Mostly these free IPTV apps takes sources that keeps changing every other week. So one has to be diligent to change app as that is how it is being done. The sources are released by the illegal IPTV sellers, in hope of frustrating users to contemplate buying subscription from them instead of the hassle of updating or changing app. This has always been the case with these free IPTV apps that comes with full channels of all major Asian countries TV broadcast.

As for Kodi, if you wish to venture into this - then highly recommended to get 4GB ram Chinese tv boxes excluding MiboxS.