This one looks best so far

Looking at it again, D#6 is really good.

Want to check couple of alternatives
1) For same color, circles sizes in reverse order
2) All circle sizes same. Possibly add text WSC/WPC/India inside the text. [ We need to put these 3 somewhere anyway ]
3) Everything same in D6, except that the smaller circles are little larger than what they are now.

Design 7 (Reworked on the logo that Amit's shared earlier. Its not as good as that one, but it gives a fair idea of how it'll look)
I can work more on this if it is good.
I like D6 better though.

I like it too, I am wondering if the Circles can get bigger and fit in the messages 12th WSC, 26th WPC and Bangalore, India respectively on each colour.

One more thing. Will we be using name of city as Bangalore or Bengaluru? We have to decide on one name and have to consistently using that name throughout.

Design 6:



Design 8:



Design 9:



Design 10:

I like Design-6 even more now, after trying out numerous iterations.

Adding WSC/WPC to this logo isn't looking nice. Will think of some other ways of including it. Btw, the logo and the text can be two separate pieces too.