I can't find reliable sources on costs for the B1B. I see some figures saying that it costs over $60,000 per flight hour and has a lot of maintenance related costs.
If I extrapolate numbers
from this congressional budget office report from 2018, it seems to suggest that each B1B in operation costs $36.8M per year in operating and maintenance costs.
That's not figuring in the acquisition costs either.
I'm unsure how much a nirbhay/prahaar/etc equivalent setup costs to acquire and upkeep.
If you're only looking at platform costs, then no, the bomber is more expensive. But if you look at all costs right from purchasing the batteries, manufacturing the missiles, storing and transporting them, using them, paying for all the personnel, costs associated with casualties etc, then costs go in the bomber's favour.
Otoh, the cost of a lease won't be much, any upgrades may give the airframes 10-15 years, which is enough time to replace it with something better.
The IA is paying 4300Cr for a new Brahmos regiment.
PGMs I have in mind are glide bombs and the like. I don't forsee any circumstances where large Indian aircrafts will be able to drop simpler laser guided general purpose/FAB style munitions and survive.
The IAF should plan for successfully SEAD/DEAD missions before acquiring nice to haves after thr mission is done.
It depends on the progressive degredation of enemy SAMs allowing the IAF to operate closer to them. These bombers are not for first day of war, outside standoff strike.
Out of curiosity, if war breaks out in 2025, how would the IAF go about suppressing the PLAAF and its air defense capabilities? It's like expecting Saddam Hussein to perform SEAD against allied forces during Desert Storm
Rafales and M2000s have to do the honours, alongside missile strikes. The MKI can contribute with standoff missiles too. So can LCAs. Armed and attack helicopters will contribute to the mission as well.
I personally don't think a squadron of strategic bombers will make much of a difference in the grand scheme as you suggest. Even if the RCS is somehow stealthy enough to get close, theres no way they will survive the threat environment for long.
The IAF lacking sufficient quality jets for cover means anything outside standoff range is basically suicide.
They will be limited in use against the PLAAF and will just suck away more resources from projects that more desperately need them. Not to mention having yet another platform, plus airframes that will be over 30 years old and heavily used during the middle-east conflicts...
It's all scenario specific. Not all areas of the battlefield will be protected by SAMs, fighters can always be engaged, and pretty much all areas of the battlefield will have unprotected PLAGF troops. Especially so post the SEAD/DEAD stage, where only the most important areas will be protected.
My first pick is just as many loitering munitions and drones as can be squeezed into the sky.
These can only complement the bomber, not replace it. And nobody can micromanage that many drones that's enough to replace a bomber or two.
If they have to buy old stopgap frames I would rather they purchase old mirage 2k.
Was the plan until all users decided they don't wanna sell their stuff to India. And if they do want to do it, it's gonna be a 10-year wait.
Or magically make HAL competent and fast track a composite framed AESA variant mki like the J-16.
10-15 year effort.
And leasing 6 bombers will cost us about $2B. How much would 6 MKI squadrons cost? And 6 bombers can rapidly be increased to 12 in no time. And now you've thrown away money at 6 MKI squadrons that will take 20+ years to induct and will remain in operation until the 2070-80s or so, draining the exchequer while remaining useless. Money that could have been better spent buying 3-4 more LCA squadrons and 6 bombers, which is a much better idea.
And a bomber still retains other advantages, like launching attacks in the SCS, projecting power across the IOR and so on.