I would like to add some thing too.
People dont want "great" front cameras... they want front cameras that MAKE THEM LOOK GOOD. Its should be renamed as "Vanity Cam"
People dont want front cameras that IS SO CLEAR that it shows their wrinkles, acnes, scars... they want front cameras that make them look like a super model. Majority, including me, use "beautify" effect on default because i dont wanna look like an ogre. Reality suxx, i wanna look better than what i do in reality XD XD
This is the reason why most selfies are taken using third part apps like Youcam,Beautycam,..etc etc and other 100s of other cam software made by Chinese software devs.
Here are some areas where Asus should focus on:
1) Good software package. Get all those awesome rear cam features to the front camera. If you can add even 50% of the features offered by rear cam, people will start using Asus's front cam software more.
2) Huge Camera sensors. Now you all may be calling me noob for this but it admit it, from marketing point of view it makes sense. HTC One M series have awesome 4mpx UltraPixel at the front.,,
better than 99.99% of smartphones out there when it comes to selfies... But if girls want to buy a phone for great Instagram selfies, they will go for the ones with 8-13mpx count, not the HTC One M series (cant blame them)
3) At least f2.2 aparture lens on selfie cam.. and make it AS
WIDE ANGLE AS POSSIBLE
4)
Boke' effect on selfie cam (sorry if i spelt that wrong), preferably with Live preview of the effect.
5) Please go easy on phone
size and weight. Taking selfies, specially group selfies using a HUGE PHONE IS A PAIN, specially for the weaker sex with thin and frail hands

. Taking picture with the new Zenfone Selfie is an effort in itself due to its bulkiness
6) Market your phones
separately for girls and guys. If you blast your smartphone ads with terms like "SUPER SELFIE" "SUPERB FRONT CAM" etc etc you are gonna alienate a vast majority of male buyers (specially the Moto/Nexus crowd who dont want to be part of the superficial crowd). Make Zenfone 3 Selfie appealing to girls (with Snapdragon 410, 5 inch screen, ultra thin, low battery, 120-130gms and super duper front cam) and Zenfone 3 Pro for guys (with Snapdragon 810,5+inch screen, thick with big battery, 150+gms , small sensor but high pixel size rear camera with TONS of Manual modes)
7) Please no 4K. Its useless. Quality is worse than 1080p...phone gets burning hot, you cant take videos for long and modern phones done have external memory expansion, sharing your videos with ur friends via bluetooth takes an entire day

. Taking a 4k video of a basketball match= internal memory full!! The current standard of video encoding is poor and inefficient. Please, no 4k please. How many of you even take videos at 4k? Probably once or twice when you first bought your phone... after that you probably never touched 4k.