Have to check ur Engine Oil leaking from which place. Original Engine Tensioner quite expensive. U can go for Gates Brand or others.

Where u service and change ur Timing Belt? Outside Workshop or Authorize SC?

It depends.. How u notice that there is oil leak? U saw oil on the floor? Identify where is it leaking out from first.. Can be from the gasket, to an improperly screwed in oil filter improper installation of oil seals.

How old is ur car? how many KM mileage.. If compressor kicks in and screeching noise comes out then most likely its belt tensioner not providing enough tension..
Hehe.. I got test test sikit.. Quite good, boleh tahan, gear shifts amazingly smooth.. But the price top up a bit can get piggyback ady.. 

Ahh ic.. For the screeching sound, high chances that the tensioner has lost its ability to provide enough tension or the belt u are using maybe of not good quality and has sag so much till the tensioner could not take up the slack of it.

As for the oil leak, its pretty obvious its the oil seals that have given way, when was the last time u changed the oil seals and timing belt and tensioner and what brand was it if u know?

Normally a proper timing belt replacement package will have
Timing belt
Drive belt
timing belt tensioner
drive belt tensioner
crank oil seal
cam oil seals
tensioner bearing

2 years mileage 120k.

Abong, u got a new competitor.

*grabs popcorn*

not necessary to use original timing belt.. They are priced more expensive than Aftermarkets and not necessarity better..
What i can recommend u is change Gates timing belt.. The whole package comes with timing belt + oil seals + bearings around RM300, then u have to buy drive belt - Bando recommended (dunno how much) and tensioner which would cost around around 150 based on ori price..

Or u can just go to EA there everything drex kasi settle.. haha..
Wah.. how much of fuel u could have saved if u modded ur car a bit to save fuel.. hehehe..

Erm bro.. haha.. Thats the standard FC for Persona lah... haha..

For FC optimization
change extractor (can change full set exhaust if u feeling rich)
Works Engineering lightened crank pulley
Denso IT20 Iridium Plugs
Works Engineering Drop-in Filter
use Cusco/Castrol engine oil..

2 years++ maa.. hehe.. got that ++
of course it is the same size, but does it been installed properly? were the quality the same as ori?
NGV no power..

Sure you want to use liqui moly, Cose say thats for diesel engine ler...

IMO, I will stick with Eneos if it runs good in your ride. Its a good lube. Price a bit on high side (is it?)

Although drop in filter is good for power, its also dirtied the throttle body much faster. That can reduce the performance of engine later unless you realise its due to dirty throttle and clean it. For me, that negates the boost at mid to later life. I personally favors changing a new filter every 10K. Way cleaner and equally power boosting.

Extractor, many favors it but that for me is not environmentally friendly and its consider a major mod. Now LCP I can vouch for as a minor mod that can effectively boost low to mid end torque (change gear faster but have to re-learn to press fuel pedal differently). IN a way save FC if you don't rev rev (since better low end torque, so FC poor coz rev more).

However if always goes on highway, I'm not sure if LCP helps coz it does theoritically lower the top end power vs stock at higher speed.