The growth of mercenaries is a very interesting development, I never thought of anything like that happening before. I imagine with the high-quality and quantity of troops, they would be hired all over the Indian ocean basin, in Africa and the Middle East and ever SE Asia like you mentioned. Was there any OTL precedent for this? Also, are the nobility represented largely within these merc companies, or would they prefer the prestige of state military? And if need be, it would seem that the hiring the Indian merc companies to fight for the Mughals could get quite expensive if they are needed on a large scale.
Money is rarely an object for the Mughal state- Shah Jahan spent 24 times the cost of the Taj Mahal in the Qandahar expeditions and 21 times the cost of building Shahjahanabad. The Great Mughal has deep pockets.
Most mercenary campaigns abroad are restricted to the months of October to May, as the mercenaries will need to come back and farm their land. As such there’s a limit to how far they can go- still they can go anywhere around the Indian Ocean, the Middle East and Central Asia, battle for two or three months and then be back in time. Longer campaigns would be limited to east Africa or Southeast Asia. Quality of mercenary troops varies, as you never know if their training is as good as the state military, but quite a few groups are very good, and there’s certainly a lot of them so they can take advantage of economies of scale. Quantity has a quality all of its own.
The state military has a great salary, and is in general more prestigious than mercenary companies, but mercenary companies can win much more glory abroad, so lower level officers gravitate towards them. We must remember, the vast majority of mansabdars (more than 95 percent) have mansabs lower than 1000, and there are more than 70,000 mansabdars- the entirety of that lower nobility is looking to distinguish themselves.