I wouldn't say that Bolster is necessary to keep Sections competitive, four-man IS with 2x Bren already stand up to Volks and Grens with no problem. It's just so powerful and cost-efficient to get this upgrade.
Increasing the MP cost of bolster would definitely drag out the powerspike Bolster has, but I'd argue that 150MP is negligable. It's not even one minute of Manpower income. Also, saving fuel on this upgrade is probably not a good idea because fuel investments are central to teching. Spending on side tech delays main tech, so you're essentially trading a later powerspike for an earlier powerspike, which is a decision that must be made by the player.
Would a concentration barrage cost decrease/cooldown decrease work to make up for the Sexton barrage?
What do you mean by "blob clearing"? If you mean destroying blobs outright, the Land Matress and the AVRE are viable options. If you wish for indirect fire, I would say that providing the Brits with the USF mortar halftrack would be sufficient.
My idea for bolster is just to delay it slightly as an adjustment instead of a major change such as moving it to company command post. MP is valuable resource in that it is required to train new squads and reinforce existing squads (especially if models are lost in combat once bolster is completed). I think 150MP is already on the high end of adding to the MP requirement. The reason why I suggest adding grenades as a requirement is because it eases the transition as you can get it earlier and while fighting and it delays *research time* of bolster as you have to wait for research grenades first. The UKF player is already significantly investing into their infantry by researching grenades and bolster and they should see a return on that investment.
The delay is 3 fold.
1. MP requirement adds delay
2. Grenade research requirement adds additional time delay
3. Reduced fuel cost to compensate not being able to tech to company command post and thus get pyrotechnics and medical supplies which is another power spike to infantry sections. I see healing in the field as very powerful. Keep in mind that not getting medical supplies means a higher MP bleed over time, using MP for medics is also another form of MP bleed.
Royal Artillery isn't even that great in team games. I find it pretty lack luster especially if your team can't hold ground. And if they can hold ground, they probably don't need (you) royal artillery in the first place. Watch PFC02 on twitch play royal artillery in random team 4v4. Most of the time if he wins, his team carries him and if he loses, its because he didn't have enough impact on the game to turn the tide as royal arty. Don't take away valentine from royal arty.
RE: Blob clearing
UKF is very vulnerable to blobs. They don't have a dedicated unit to deal with blobs. They can't punish blobs in the same way that other factions can without doctrine units.
They either have to counter with their own blob (and be susceptible to enemy blob clearing units) or go a specific commander to deal with it and this is not something you can predict will happen in the game. Outside of what I mentioned before (mortar pit/land matress), you can also try running them over with a Cromwell/Comet but thats a great way to lose your Cromwell/Comet if they have a snare unit in their blob.
I will list the blob clearing units of other factions that do not require a commander.
USF have Sherman HE, Pack Howie, Mortar Carriage.
Soviets have katy, demo charges.
OKW have IG gun and stuka. Stuka arguably the best blob wiping unit in the game.
OST have MG42, Brumbar and Werfer. OST have it good in the blob control department in regards to suppression. I don't mention the MGs in other factions but the MG42 is the best in the game for suppression and the werfer is the fastest out of all rocket artillery and includes suppression.
UKF has a mortar pit which can be easily destroyed by any other blob clearing unit. Building a mortar pit is kinda like a double edge sword. You can fight blobs within the mortar pit's range but the enemy can get a blob control unit to destroy the mortar pit and then they can't blob to fight the enemy blob. In addition, you have to put a squad in the mortar pit to make it fight better which is a great way to lose a squad.
I didn't mention pyrotecnics as a counter but that comes waaaaay too slow and has a very obvious indicator of where its going to land for it to be an effective blob countering tool.
The only effective method I have used to counter blobs is a vickers MG in a trench but it can be easily countered by moving around it, smoke or indirect (such as a stuka). It doesn't punish blobs, only suppresses it so you can deal with it using something else.
Edit: Forgot about Brumbar
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