If you are sure about your interest in CSE, DTU is the best option for you. However, if you are yet to identify your area of interest then go through the following parameters

• Placement: DTU has ties with huge CSE companies like Amazon, and Microsoft that offer excellent packages to the students even better than Civil at IIT Roorkee. I know many friends from NSITs and DTU that work in Microsoft today.
• Research: The CS department is undoubtedly better in terms of research work and opportunities than the Civil.
• IAS: For IAS, the most preferred branch is Civil. However, if you do for Roorkee, you will have limited options for coaching which can be easily sought at IIT Delhi
• MBA: Again, because of better coaching institutes, IIT Delhi is better to prepare for CAT.

Once you are sure of your inclination making a decision won’t seem so difficult!

Both IIT Mandi and IIT Ropar are well-respected engineering institutions. The institute which is most suitable for you depends on your individual needs and preferences. Some parameters you would like to consider are location, campus culture, research opportunities, and faculty expertise.

In my opinion, IIT Ropar fares better in terms of infrastructure, college life, labs, and resources. IIT Mandi on the other hand is lacking in terms of infrastructure and its campus is still in the development phase. The facilities and infrastructure are crucial to a conducive learning environment and IIT Mandi has failed to do so. IIT Mandi is also located remotely and thus students cannot avail of facilities easily and the exposure offered is also limited. IIT Mandi labs have failed to meet IIT standards and are decked with outdated equipment.

The labs of the School of Engineering and the School of Computing and Electrical Engineering are not at all good and have very limited operational capacities.

Keeping all the above factors in mind, it's better to go for IIT Ropar. Additionally, it is recommended that you visit the websites of both institutions and speak with current students or faculty members to get a better sense of what each has to offer.

IIT Indore is one of the leading new IITs that has made its name because of its multiple achievements. Here is exactly why you should give more preference to IIT Indore than IIT Patna. 

• The faculties are very approachable and cooperative. They guide you to do projects and even motivate you for research work. Additionally, they teach you tactics to clear GRE and GATE for top universities and PSU respectively. Such kind of guidance isn’t available at every institute.
• The faculty-to-student ratio is great around 12 - 13 faculties for 40 students. This helps the students to get individual attention from faculty who track the personal and individual growth of every student. 
• IIT Indore has ties with the University of Stuttgart, Germany enabling students to do internships in the second year. 
• The students' demands are given due importance and the HODs bring all necessary changes demanded by the students to make things easy. 
• IIT Indore being new has top-notch labs with all modern equipment and instruments.

In all, IIT Indore is a great choice for Civil Engineering.

I will restrict my answer to Engineering Physics and Chemicals only as I know the same only. 

• The major criterion followed at IIT Delhi by all the branches is a well-maintained CG. To secure good placements one has to constantly score a good CG throughout the program.
• During your admission, the department does not play any role but your 85 percent constraint on minimum possible strength does.
• Engineering Physics is a unique branch for those highly passionate about Physics and want to pursue higher studies in the same
• To secure core jobs, one has to move to MTech in Engineering Physics from BTech in Engineering Physics.
• For Chemical Engineering students, BTech is more than enough to secure decent packages and great research opportunities outside India.
• Consultancy and Analytics jobs are offered equally to students of all the departments 
• Engineering Physics graduates usually take up consultancy or IT jobs 
• Chemical Engineering is the most laid-back department of IIT Delhi with very flexible academics thus making it easy to maintain a decent CG throughout. 

I wouldn’t suggest anyone go for Engineering Physics if they have no intention of pursuing it later. Instead, look for other options in BTech and explore your interests.

Honestly speaking, this internet-controlled era hardly requires good teachers as everything is available on the net. You can get in touch with internationally proclaimed professors with just a click. As far as IIT faculty is concerned, all IITs have similar degree holders that are quality knowledgeable. 

A good teacher is the one that hones your talents to the fullest. They not only help you acquire knowledge but also shape your thinking style. Every institute has a few teachers that influence a student in a unique way. I am sure both IIT Guwahati and IIT BHU will have similar teachers. 

Ultimately, what matters is the environment and the activities that these colleges will provide us to expand our intellect and maximize our talents. Pay little focus on the faculty and look for the right field to enter that will help you shape your career. Personally, I would suggest you go for IIT Guwahati as it has more open-minded and active people in that area which will give you considerable freedom to think and perform.