That was something we really didn't like the standard US Army Inf Sqd as I outlined above was going from 11 troops to 9. 11 gave you 9 dismounts with the Driver & TC staying with the track(113).
The M2 Bradley Sqd had 9. 6 Dismounts, with the Driver, Gunner & TC stay with the M2. Now you do have more firepower, with the Bushmaster & TOW on the M2 vs. the M2 .50 on the M113. True enough.
But as any Mech Infantryman knows the track can't go a lot of places the troops on the ground can. That is true with both the M113 & M2.
Of course the tracks can set up a support by fire position to provide cover, etc. to the dismounts. But you can't take a track too far into a swamp, thick woods etc., many places where Grunts can go. Like many things on ops it's terrain and situational dependent.
I know e.g. the Infantry in the BMP is supposed to fight with direct support from the track. But just like with the M113 & M2. You can't take a track everywhere. I'm pretty sure they experienced this conundrum. Of course I never served in the Russian Army … so …
And again as well trained Infantrymen know, on patrols of all types generally you are dismounted. Tracks/AFVs make noise. Many times you don't want that if you are patrolling, or moving on the ground. Your mission depends on stealth, light & noise discipline, cover & concealment, etc.. Grunts can hide fairly easily. Tracks/AFV in many cases, again based on terrain, can't hide as easily.
I know as Rifle PL in the 101. We were normally moving dismounted. Thru some thick foliage, flora, etc. Then later as an M113 Mech Co. Cdr, we had to do the same. In both cases a dismounted night attack could be very successful if done properly by well trained & experienced troops.
With Mech many times we'd move dismounted to an OBJ, etc. Then the Tracks would link up with us later/when called forward.
Based on my training & experiences I think 6 dismounts may be a bit small in many/most cases. You add losses, e.g. injures, illness, KIAs[God Forbid!], etc. Your 9 or 6 dismounts could rapidly be reduced. However, with only 6 to start out with you may end up with two 2 man Fire Tms or one – 3 man Tm(!!!!!!).
Just like sometimes with a [US]football team you won't have much depth on the bench. Which may impact what's happening on the field …