I don't who is that idiot , but small balance ? SG counters BG and everyone knows that , he obviously don't know shit what is he talking about.
It's the rock/paper/scissor triangle , SG mostly beats BG , BG mostly beats Leader Mercs but Leader Mercs counter SG. The problem is you are most likely to encounter a sniper than a leader merc. How do you balance that ? I believe BG needs better odds against SG. There are many ways how to accomplish that you can nerf SG or boost BG , or add new perks , or new " mechanics" ( or any of these variations mentioned) for example like solar said that AC could interfere with opponents crit chance.
Now the million dollar question is how to balance , not what to balance ?
Even Solar cannot be certain , because many Solar posts contain words like might/i think/should/I believe/could etc. etc. , those words do not express certainty.