It has been long time since release of last mid-range device (Zenfone Max Pro M2), so I have ideas for next mid-range :
1) First of all, shift to Android One, because previous devices had bunch of bugs which can never be solved.
2) Mediatek Processors can be used (like Dimensity 820). I don't know what actually happens internally, but both Asus & Mediatek are taiwan based companies, so maybe effective price of processors can be reduced. (Don't judge me, I said "maybe")
3) Asus has a good experience in system cooling (ROG series) and Mediatek is known for heating issues in the devices, so why system cooling can't be implemented. ( Like liquid-cooling in Redmi Note 8 Pro equipped with Mediatek G90T )
4) Atleast 6.5 Inches FHD+ display ( IPS LCD Panel with Punch Hole Camera & 90/120 Hz refresh rate ) or ( sAmoled Display with notch or pop-up camera with 60 Hz refresh rate )
5) In camera department, 48 MP Sony IMX586 can be equipped with Super-Wide Angle Camera with Auto focus for Macro Shots as well and a portrait lens. For Selfie, 16 MP camera is enough either as Punch-Hole in IPS LCD display or pop-up/notch in sAmoled.
6) In terms of durability & design, it must have a Glass design (Corning Gorilla Glass 6) with gradient design.
7) For Security, Fingerprint lock must be Side mounted in power button in case of IPS LCD display or in-display in case of sAmoled.
😎 Battery must be maximum upto 5000 mAh along with 22.5 W charger.
9) Now, if I am not wrong, the price of 6GB RAM/ 128GB ROM variant (if comes with IPS LCD panel) must be 299$ globally (for European market) and in case of Asian market, it must be around 249$ as much as possible.
Dear Asus, Asian countries has a lot of potential, especially India, where Chinese products are being boycotted.