While we are waiting for LCA MK-2 which would be the type what IAF wants, it would be better to have a look at the philosophy of hugely successful production run of F-16 program of US.
Just checking Wiki entry on variants of F-16 throws up interesting insight ( we knew but do not follow)
production of F-16 was in Pre-production and Production variants.
Pre-production had two variants YF-16 (two prototypes) and F-16-FSD which was ordered by USAF totalling 8 in number.
Thereafter , it has gone into full scale production in Blocks. Each successive blocks denote minor or major changes in F-16
The first off the lot was F-16 A(single seater) and F-16 B( twin seater) ( blacks 1-20)
F-16/A -375 nos
F-16 C/D Block 25 209/35 nos ( radar, avionics and FCS, MFD, precision night attack capability.. etc)
F16 C/D Block 30/32 733 nos ( included export variants) ( INS, GPS, Litening Pod, New engine,JDAM,improved EW Suite..)
F-16 C/D Block 40/42 615 nos (exported)( LANTRIN pod,, NVIS, JSOW, WCMD, Paveway etc)
F-16 C/D Block 50/52 and +
F-16 E/F ( for UAE )
F-16 A/B Block 15 ADF
F-16 A/B Block 15 OCU
F-16AM/BM Block 15 MLU
F-16C/D Block 30 F-16N/TF-16N For NAVY
F-16CJ/DJ Block 50D/52D For SEAD Mission of USAF
F-16C/D Block 52M For Greece
F-16 Özgür For Turkey
F-16I Sufa For Israel
A-16 For CAS ( Not produced)
F/A-16 Retrofitted existing F-16 Block 30/32 for CAS and BAI
F-16A(R) for Netherlands
F-16 Recce Reconnaissance variant
RF-16A/C For Danish AF.
There are other variants also listed and many are country specific ( as also quoted above)
Clearly USAF was on board fully to give bulk orders in initial lots and later secured huge orders from other countries. Each successive blocks featured enhancements or major improvements from its previous iteration and as and when new tech became available.The cost of development got amortised easily due to huge orders. This is one highly successful programe of US . I am quite confident that we could adapt these philosophies to suite our needs and requirements and develop a successful LCA program in Block mode.
For full details please refer to wiki entry https://en.wikipedia.org/wiki/General_D ... n_variants