To me sections are fine. Brits have great versatile infantry. I always use bolster. As UKF you must play like ostheer and use the full power of sections AND mgs. You just can't play them like USF or Sov. Sections can easily carry you to next stages of the game and remain your staple infantry. I can't imagine a scenario where realistically speaking you don't put sections in cover where they are boosted. In their "natural" circumstances and when properly supported, they rock.
When it comes to testing - one should test all scenarios and only then draw conclusions. You can't set up a test in probably the only scenario when a given unit loses and use it as an argument to boost a unit. A risk of unbalancing is too great then.
I think for the cost and getting their nades and lmg,s and punishment out of cover they are slightly up.
Your pay for a 5 men squad but get 4 men until you pay more. The 2mp less reinforce cost and sandbags dont cover that completely.