Arjun, of those listed above, I have only seen Bhatia bowl but I would wholeheartedly agree with Manee. He'd be little or no use at international level, bowling mid-70s would just end up in a torrent of boundaries. Multiple-skilled cricketers are only ever good when one of their skills is at or very close to international standards; Bhatia would get nowhere near the side in either discipline. And IMO it would be dangerous to present them as better options than Sehwag/Yuvraj bowling 10 overs, since you're judging one set of players purely on their performance in domestic cricket and the others on performances against the world's best.
I didn't elaborate on this last time, so I'll tell you the whole thing.
To begin with, they already have Irfan Pathan, who's genuinely good with the ball. Unfortunately, he's gone off the boil again, for some reason, despite coming off splendid domestic form. However, with no replacement in sight, the Indian team is a lot weaker, and are forced to go back to him all the time. I was suggesting one of these as a short-term option until they get Irfan back in wicket-taking form. Yes, Irfan is different from any of this bunch, but the objective is still the same. This is a selection to get in two Indian spinners in all conditions, in Tests and limited-overs matches.
They only bowl in the mid-70s, but they do a good job of it. We've seen bowlers from most teams, including India, who bowl fast, but bowl utter rubbish and lose their (and their team's) advantage. Dilhara Fernando is one great example, then the now-retired Mohammed Sami, and of course, RP Singh, Munaf Patel and VRV Singh. Bhatia and Nayar, on the other hand, bowl sensibly.
Likewise, we find several bowlers (including specialists) from other teams who bowl in the 70s, have the keeper standing up and do a very good job. This is because they bowl sensibly. I can name a few- Scott Styris, Jacob Oram, Grant Elliot. They're slow, but accurate and smart. Jesse Ryder was very difficult to get away even on a flat wicket. That's something we can expect from Bhatia and Nayar as well. Just because they're Indian and they've succeeded in the Indian system doesn't make them so much worse. Moreover, the Indians don't have too many genuinely good pace options who add value to their team.
On the other hand, you have at least three talented specialist spinners- Harbhajan, Mishra and Ojha- and two often miss out because of the team's decision to play only one spinner, leaving the rest of the spin duty to the part-timers. Consequently, they either miss out on an advantage to take wickets when they're on top, or they are sitting ducks for a team batting well. We often see them being handled with kid gloves while the tougher tasks are given to the main bowlers.
That the part-time spinners have performed in international cricket is immaterial- they've hardly been full-time bowlers, and playing them as such is a very big risk, especially outside India's spin-friendly pitches. Looking at their domestic figures, we find they're not even regular bowlers in the domestic circuit, unlike the seam-bowling batsmen. Moreover, Sehwag and Yuvraj are your top batsmen. You need big hundreds from them. They should be allowed to concentrate on their batting, without getting them disturbed by calling them on to bowl, and letting them get thrashed, or worse, fatigued. We saw Sehwag bowl loads of overs and then get out for zero. The seam options are used to it, and they're not your best batsmen.
Ultimately, it's more or less an interim arrangement until they get Irfan back.