Firstly let me clarify one thing. IIM Raipur cannot be compared to IIM Shillong because the latter is out of the league and is no longer a new IIM. Its worth and placements are much better than the newer IIMs and are in the league of old IIMs. We can only compare IIM Raipur to the 6 new IIMs namely Raipur, Ranchi, Rohtak, Trichy, Udaipur, and Kashipur.

After Shillong, one new IIM that gives an edge to older IIMs is Ranchi mainly because it works under the mentorship of IIM Calcutta. The placement statistics of IIM Ranchi are a testament to the same.

After Ranchi comes to Trichy, one of the fastest-growing IIMs. It has a decent placement scenario and a better professional approach.

Raipur and Udaipur are almost similar and are better than Kashipur and Rohtak. Raipur especially enjoys location advantage being situated in the capital of Chattisgarh. The faculty base is also quite learned and the institute has proper connectivity.

Kashipur has many connectivity issues but is famous for its guest lectures and interaction with industry experts. 

IIM Rohtak is the last in line mainly because of its pathetic placement scenario which overshadows its vicinity to Delhi.

So the final order is

Shillong>Ranchi>Trichy>Raipur=Udaipur>Kashipur>Rohtak

The distinctions between Ranchi and Trichy are razor thin. Both second-generation IIMs are performing admirably in their respective leagues. Here is a comparison of Ranchi and Trichy based on various parameters. Raipur and Kashipur lag far behind these two IIMs.

Parameters:

• Placements: Ranchi and Trichy have remarkably similar placements. Ranchi's average package is 16.62 LPA, while Trichy's average package is 17.01 LPA.

• Campus: Trichy, hands down, for campus life. Trichy has a modern 175-acre campus with all amenities. In 2021, the institute began moving to a permanent campus on a 60-acre plot in Dhurwa.

• Locational Advantage: Both have a geographical advantage. Ranchi is near XLRI, Jsr. Trichy is conveniently located between Bangalore and Chennai. Trichy is also home to NIT Trichy, the best NIT in the country.

• Perception: Trichy's perception is rapidly expanding. It is fairly obvious from all B-school rankings. So, with the exception of marketing, you can choose IIM Trichy over IIM Ranchi for any specialization. Ranchi's marketing is effective.

Therefore, taking everything into account, the final ranking will be Trichy>Ranchi>>Raipur>>Kashipur.

Your choice of college depends on your personal preferences and interests. One college might be suitable for you but not for others. So your question is subjective and cannot be answered directly. 

Every individual ranks a college depending on his own perspective and goals.

I think the best way is to contact students or pass-outs from respective colleges, collect data and then make a decision based on your research and then your preference. You can also look up the official websites of the college to collect relevant data. Find out the parameters that matter to you the most in your choice of college. Some include placements, diversity, location, batch strength, or faculty. Do your part of the research and then choose the college that fulfills the maximum boxes in your priority list.

I think the single most important reason why IIM Raipur and Ranchi are considered below IIM Udaipur is the lack of proper marketing. IIM Udaipur has managed to make its mark through enough marketing and promoting research culture. The IIMRs is also flawed in the sense that they are located in extremely poor economic states. This flaw overshadows all their features and the fact that they have better placement scenarios than IIM Udaipur.

Every IIM has set a certain goal and is gradually climbing the ladder to reach its level of excellence. The same is the case with IIMRs. In just a few years these two will be among the best IIMs in India.

Every ranking is done on the basis of different parameters. So we cannot define the worth of a college just by looking at one or two rankings. IIM Udaipur has been featured in both the QS and FT MiM rankings which included only the top A B and C IIMs. The QS ranking focuses on the research culture mostly in which IIM Udaipur excels at. Its excellent research contributions has brought it in the league of the top 3 IIMs. But the FT rankings do not have only research as their parameter. So we can say that IIM Udaipur indeed is worthy of its position and rankings among the top IIMs.