1NZFE - the most boring engine?

[SlowVitzRS]

I currently drive a JDM 2005 Toyota Vitz RS 5-speed manual as my daily driver.
I find it hating more and more every day I drive it :(.
There will be a point where whatever the fuel savings over my other car will not be worth from mental health point of view.

Scroll down for the actual questions if too lazy to read ;).

A bit of my car back ground:
Due to my previous jobs I have driven hundreds of make/models, and many more individual cars.

I used to be hardcore Toyota fan, and personally owned couple of GT4s (still have my ST165, sold my ST205), couple of 4AGE powered vehicles (AE91 and AE101), also had 4AGZE AE101 for short time, some other odd balls passed through my hands like MTEU, 1GFE, 4/5AFE, 4EFTE, 5EFHE, 3/4SFE, 1ZZFE, 2ZZGE, 2AZFE powered cars. So I have huge preconceptions and bias about what to expect from Toyota engine.
Currently there two 1NZFE Vitz RS in the family: CVT and manual.


Before you go "Cool story Bro", I am going back to the problem at hand:

1NZFE - is the most boring engine I ever owned. The manual transmission actually brings out the all downsides of this engine. The CVT one actually feels better than the manual one (blasphemy!).

It has power curve of a diesel without the low end torque. It feels very asthmatic. No, this is not confined to this particular car. It feels that Toyota designed this engine to be coupled with a CVT or hybrid transmission.

The factory 1NZFE on a manual transmission equipped car comes with really dull throttle map. From my experiments the throttle response is identical on CVT and manual equipped cars.

I have addressed the throttle response by switching throttle body from a 1ZZFE. Now throttle response is excellent.

Another issue is the plastic manifold completely ruins the induction noise. I have addressed the restricting snorkel, which slightly improved top-end, and under high load there is a small hint of a typical twincam noise (listen to 4AGE, 2ZZGE or any Honda twin cam engine), but because of crappy econobox intake manifold it is ruined.

The transmission gear ratios are too high for it, it feels like the gear ratio is more suitable for something that revs to 7000+ rpm (in fact I think it is very close to AE101 4AGE 20v). For such low rev limiter that 1NZFE comes with, the gear ratios should have been much closer.

Why did Toyota put "RS" badge on it is beyond me, it is actually same performance as non-RS 1NZFE powered Vitz.

Even 2AZFE powered Camry that I had "pleasure" of renting and putting about 6000kms on it, was more fun to drive.

At this stage I am looking at mild cams, and fabricating intake manifold. I am not actually after raw performance (I own couple of cars that make 200+ Kw at the four wheels), I am after a fun pocket rocket that I can enjoy driving.

Any ideas what could be done to improve the power curve (read: move torque peak higher in RPM range) without changing the ECU?
I would love to have it sound at least decent (iconic twincam induction noise), without resorting to after-market filters.

Does anyone know where to get mild cams that will work with stock ECU, and aluminium intake manifold that works with 4 bolt throttle body (I only seen 3 bolt version)?