Finally, I'm back with some news.
I end up getting a new Polygon Siskiu T7 back in April, took a long time to decide also a long waiting period, big hole in my pocket.
Since then I had done some upgrade, a few knicks and knacks like adding mud guard front and back, lower the handlebar height to try out some setting and the major ones are replacing my stem and saddle.
I replace the saddle due to the one came with the bike is a bit narrow for my butt and butt hurts, fat guy big butt.

Bought a Selle Royal Float Athletic.
As for the stem, I had the original over torque and the thread line are gone for one of the nut. Replaced with a Spank Split Stem same length no rise. And because of that, I had to purchase new spacer.
Anyhow, I have been riding it for training my stamina and short off road riding at an estate trail I found near my taman.
Overall, I like the bike, the built quality feels good and the components came with it is good.
I have a question to ask, I found online that if my saddle setting is right, when my feet are level on the paddle (right leg in-front and left leg at the back), my right kneecap and the paddle's axle should form a straight line. After installing, setting the saddle height correctly and moved the saddle rearward as much as possible, I found that I still can't get a straight line between my right kneecap and the paddle's axle, it is around 2~3cms forward than the axle. Has anyone facing the same problem? Beside getting a new saddle or even a new bike

, what else can I do? How will it affect my ride or kneecap if I just leave it as it is?

Congrats. Nice bike. This is the beginning of the end aka spending more money on upgrades/new parts!
Kinda hard to visualise your seat and feet position based on your description. Can take a pic? Anyways, have you tried it on the trails yet? How does it feel? As long as your feet is almost fully extended at the lowest point, that's ok.