Isn't FWD abit more fuel efficient, more leg room and also less prone to oversteer
Not against RWD but majority manufacturers have migrated to FWD, except for BMW and Merc.

Don't worry bro. Umw Toyota still sells the Avanza RWD.

Less prone to oversteer, but you got understeer problem also. 
The only explanation that more & more cars go for FWD is just because of overall packaging and cost.
Nowadays majority people more concern about inner interior space & fuel economy and not much in term of driving dynamics. 

expecting price tag @ 65k to 75k for 1.5NA ?

Well, in previous RWD Avanza some people manage to drift with it.. 

Wonder how long more for this, even the old alza got extended...

I have used the current/old Alza for the last decade. Yes it is a stretched up Myvi. No I don't think Avanza is any more of a 'proper' MPV than the Alza. The Alza has either huge amounts of mid-row length (compared to what affordable sedans give you) and a spacious boot, or decent mid-row length and an additional 2 seats for smaller sized occupants (good for children), with a small space for essentials (not luggage). This new Xenia, interior wise, is almost identical to that!

Avanza is based on Veloz not Xenia I think, so obviously a different comparison (price also not comparable).

Not a real SUV. Maintain the Perodua tradition of underpowered vehicles.

Very subjective to different people.. Some might suit to driving bigger cc or turbocharge vechicle.. 
I believe hill climbing might improve a lot as with the CVT gearbox it is more easy to drive up hill due to variable ratio.

this i agree..if cannot climb, i don't think they simply cincai launch the car one right?

Tested today, drives like a 2nd gen Vios. Doors and boot feels extremely flimsy but engine output surprisingly enough grunt to go slight uphill with 5 onboard. The back row is not sempit, quite ok if middle row adjusted midway and felt quite at ease after spending 15 min at the back (178cm tall)

However am extremely turned off by thd hugh engine bay gap.
Do you guys intend to cover it up?

Agree on the back row. For short distances I think will have no issue (give and take a bit with middle row people) even for tall passengers. Of course not Penang drive.
What's the disadvantage of that gap? Not really a car person, but for me... not visible from outside, does it matter?