What is the benefit of bitcoin core?
Bitcoin Core will signal support for and recognise SegWit enabled blocks, amongst other additions. Depending on your stance in the max block size issue, you might like to consider using one of the other many bitcoin clients such as
https://www.bitcoinunlimited.info/ which supports bigger maximum block sizes as a solution to the full blocks we currently are experiencing.
What client you run has zero effect on what becomes the new standard which is determined by a majority of
miners only. You're free to use whatever client you want though, it's like publicly showing your support for a political party but not having the right to vote...
i remember that merchants have an impact as well maybe not directly but they will influence miners decision, if for example the majority go with a specific side, either way at some point miners will be forced to do a decision...