I did have a look at some 100 pictures and noted how much would they be helped by one of the following features
Cem, do you really think that you can judge your needs by looking at 100 photos? Such a tiny number is probably not going to help you to make an informed decision.
Furthermore, such an analysis tells you what you
needed, not what you
will need. How will you evolve? What are you aiming to do? Think about the type of photos that you want to take in the years ahead.
This is asking a lot, I realise. If you're anything like myself, you're probably asking for help because a) you like to make a good investment, b) you can't afford to make the investment that your heart's telling you to and c) you're worried about regretting your decision.
So, perhaps a good solution would be to buy a second hand 70-200 f/4 IS, knowing that you should get back what you paid for it. This will allow you to test it free of charge for a year

After a year or so of use, you'll be able to answer these questions for yourself:
1) Is the focal length what you need?
2) Could you carry a heavier lens?
3) Did you use IS a lot?
4) Were you frustrated by the low-light capabilities?
5) Did you need to isolate your subject more than f/4 would allow you too?
6) Did you use all the range, or are you butting up at either end?
7) Would primes meet you needs better?
Etc.
By buying it second hand with the knowledge that you
will change it if needed, you take all the stress out of trying to make a decision that you simply can't reliably make today.
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Tim