Now, contrary to my earlier musings, I don't believe it is necessary (or even prudent) to aim to build square combat teams all the time.
I could see an ideal CMBG (or CABG?) with the following manoeuvre elements:
2x Mech Inf Bns (3x Rif Coys, 1x Cbt Sp Coy)
1x Tank Regt (4x Saber Sqns, 1x Cbt Sp Sqn)
Bde manoeuvre is provided by 6x Mech Inf and 4x Tank sub-units, serving under 3x unit HQs. In the offence or defence, the math the Army is looking at as a max right now is 12km of frontage. I need to dig into frontages based off recent historical studies a bit more, but my gut tells me that nothing has significantly changed the range of a dismounted infanteer for the last half-century - the platoon can still probably control a good 600 to 800 meters of ground. Sure, weapons ranges are a lot longer - but that doesn't guaranteed you anything, especially with the effects of microterrain in masking an enemy's movement.
I'd argue that you probably would want to avoid a 12km frontage if you could, with 6km for a Bde Gp as a "start point" likely being a lot more workable. With a 6km frontage, two BGs could cover 3 km each, with BG task organization being completely dependent on the task - I attached a PPT with a few different combinations.