Assuming you have 80-90k of your budget left post X2700H purchase. There are two ways you can go about it , go slowly getting a 3.0 or 3.1 setup to start with , add surrounds followed by ceiling speakers or as you mentioned get a 5.1 setup first which might need a little budget extension just because of the sub. I would suggest the below alternatives
i) Front speakers - QAcoustics 3020i ( ~25k discounted) , Dali Oberon 1 (~35K discounted) , IndiQ Platinum Mishra (~34k MRP)/ IndiQ Custom LCRs , Elac Debut 5.2 . Out of these I am not too ken on Elac's especially for movies and my personal preference would be IndiQ Custom LCR/Qacoustics 3020i . However best to audition and then take a call instead of relying on my or any other forum members opinion entirely
ii) Center speakers - Depending on what you go for above - QAcoustics 3090i (~15-17k) , Dali Oberon Vokal (~33k), Universal Aakar (~17k) , Elac Center (~25k) . Best to buy the same brand and preferably same series too.
Considering you have spent about 50k of your budget on fronts + center. That leaves you with need for a subwoofer and surrounds, options suggested would go beyond your remaining budget but will be worthwhile long term
iii) Subwoofer - Important to get a sub which has clean and deep bass , extends low to enjoy the desired rumblings during explosions , bullet shots and normal LFE induced scenes otherwise. I would suggest to go as far as possible for a good sub
~ 30k budget - Yamaha NSW300, TAGA SW 212 , ELAC Debut S10.2, Polk HTS 10 etc . These subs are decent and can be considered if on extremely tight budget, but other a no go and would recommend to look at upto 50k
~ 50k budget - Qacoustics QB12, SVS PB1000 (I believe this is much more costlier now) , BIC America PL200 II , Polk HTS12 . These subs dig deep enough and are good , would suggest to consider these over the 30k subs if possible
Please note that you can go for any brand here , not neccesary to match with speaker/center brand even if dealers suggest otherwise.
iv) Surrounds - Nothing particular , you can get anything in a budget of 10-15k here , not neccesary to match with other speaker brands. Can go for Taga 806.
