I think a good option worth exploring would be to team up with the French and Germans for the FRCV.
We can provide the quantity, which the French and the Germans combined would never be able to come up with.
An indigenous effort would be preferable, but given the whole Arjun saga, it would seem we would be stuck with doing screwdrivergiri for Armata and getting screwed in the process.
The French and the Germans have teamed up to produce their next generation tank. Neither country will be buying more then 450-600 tanks at best.
We can team up with them, with assembly of all tanks taking place in India.
From the tech that is already available and individual strengths, following can be the break up of each countries contribution:
1). Main Gun - Germany. Rhein metal has developed a new 130 mm smooth bore gun. This ought to be the most powerfull MBT gun available.
2). Engine and transmission - Germany. MTU 893 or follow on model, 1500 HP engine is ready. Renk transmission is ready.
3). Turret based Autoloader - France. The Leclerc autoloader is already available.
4). TI sights and sensors - France.
5). Chassis and Armour - India. The Kanchan based next gen armour will be as good as any available in the world.
6). Track and wheels -India.
7). ERA Bricks - India
. Active Protection System - To be Developed. Would have to be a joint effort. However, I suspect the French would have the lead in this, given their expertise in radars and sensors. DRDO can contribute given that no one currently has a system available and the APS will not consist of a single element, but a combination of various sensors and counter measures.
9). Fire Control Software, Ballistic Comp. etc. - Germany. The gun being from Rhein Metal, the software would also be from them.
10). Ammo - India/Germany. DRDO can develop a Thermobaric round for a 130 mm gun along with a CLGM missile for 130 mm. The increased diameter would easily offer a 7-8 Km range for CLGM. Maybe we can also develop a ICL-20-HMX cocrystal based propellant for the FSAPDS round. The tungsten penetrator can be supplied by the Germans. ICL-20-HMX based propellant for a 130 mm gun would give the most powerful FSAPDS round in the world. If not, for our own requirement, the FSAPDS round would be developed and produced in India. The gun FCS and Ballistic computer data would have to be provided by the Germans.
11). Quantity - India - 1,800, Germany and France - 450-600 each.
12). Manufacturing - Final assembly in India to reduce the labour cost. Maybe we can get MTU to set up shop in India to produce the engine.
A production run of at least 3,000 tanks would help lower the cost of the tanks. Plus, given the combined influence of Germany, France and India, we might be able to sell a few hundred of these to the Gulf Monarchies and others, as the latest and greatest tank in the world.
That would give us a good production run or anywhere between 3,500 to 4,000 tanks.
From the list above currently we have the tech for the gun and the related software. However, given that the Germans already have a 130 mm smoothbore gun ready and given Rhein metals expertise, we would have to accept the same, rather then go for an all imported Armata.