Iran does not need a "light and simple" fighter. Iran needs a semi heavy to heavy jet fighter to replace the timeless F-14. What will a light and simple fighter do for Iran?
A light and simple fighter can provide the numbers needed to adequately fullfil air force task, backing up and complementing larger more complexe fighter aircraft and freeing those up for dealing with key threats or crucial tasks. I'm assuming a hi-lo mix here.
It can also provide a modern design, incorporating progress made in aircraft design and engineering.
It can provide young, new airframes rather than refurbished and/or rebuilt but ultimately still old airframes.
It can provide a relatively easy to fly aircraft for less experienced pilots to become more experienced in and grow ready for the bigger aircraft.
By the way, 'light' does not necessarily mean 'simple' anymore. Simpler may mean cheaper though.
F-CK-1D was promising fighter but due some political pressure , this fighter was limited ... this fighter would become something like F18
The Indigenous Defense Fighter (IDF) program for an air superiority jet fighter with multirole capability
was initiated when the United States refused to sell the F-16 Fighting Falcon as well as the F-20 Tigershark (which had been developed largely to meet Taiwanese national defense needs for an advanced jet fighter to replace their older F-5 jet fighters)
to Taiwan following diplomatic pressure from China. Taiwan therefore decided to develop an advanced indigenous jet fighter.
The first successful test flight took place in May, 1989. However, the ROCAF's initial order for 256 aircraft was cut to 130 in 1991, following deals for the purchase of 150 F-16 Block 20 A/B and 60 Mirage 2000-5Ei/Di with the US and France.
In 2001, it was reported that development of a new "stealth" variant with more power engines and improved fire-control system would commence that year. The upgrade would allow the IDF to carry an additional 771 kg of fuel. In addition, it includes an improved avionics suite, retrofitted electronic warfare capabilities, and new weapons systems. The landing gear has been strengthened to accommodate the additional payload and fuel, but the plan for a dielectric radar-absorbing "stealth" fuselage was dropped due to concerns over weight. As of 12/2009, 71 F-CK-1 A/B are upgrading to F-CK-1 C/D over 4 years span.