Profile of DarkDanie

Recently started to play UKF in 1v1 and right now "just" level 10 at rank 330, so my commend might not be that valid. Anyway, by my experience UKF is sometimes rather strange, yet it is a viable faction. For me the key is to play quite preserving at the beginning and rush for a key building rather then cap terretory. IS are argueable the most durable mainline inf once within a garrison and volks or grens trying to rush your position will end up loosing. This gives you then the space to cap territory after their retreat. For inf spammers, there is always the vickers and UC with vickers upgrade. This allows you to trade effectively and keep the enemy suppressed. Also Brits have the fastest tech, even with upgrades. Making use of this enables the rush for a cromwell before your opponent even has set up the Schwerer or teched for battlephase 2 and gives you the opportunity to set up for a finishing blow (e.g. base rush).
For the AEC part: the AEC gives you the dynamic the UKF opening lacks. Even if you are getting rushed by a Puma, as long as your AT units are positioned well, you should be able to get the AEC out or even better defeat the puma. Furhtermore, going for the upgrades and using the abilities is also the key to victory, considering all the awesome toys UKF gets with their doctrines and the advantages of five man IS using double bren.
In general, I have the feeling that people do not get the general concept of this game. Axis as a lategame faction should win in lategame (for all those KT is op guys). In the same manner SU and USF are strong during early to mid, therefore their tasks is it to defeat the opponent during the early game. UKF however, have a weak early with a strong mid and some highlights for the late game. So my advice would be not to create this boring monotony of similar faction and actually start playing around the strength and weaknesses of the five factions as well as using tactics.

TL;DR
UKF needs to be played defensively first, needs to make use of cover and then use the fast tech to beat your opponent in the mid game.

They seem to be more of a generalist unit, supporting your stock units. For instance giving cons some space to breath by drawnig fire away from them and dealing dmg with ther DP or pinning a tank for penals to close the gap and throw their sticky satchel at them. However, it might be usfull to make them spawn with mosins only and an option to upgrade them with either DPs or PTRS only. To keep things attractive, combine the respective upgrate with abilities like PTRS upgradet guards get the blindfold ability, while the DP ugrade gets an ability to supress inf similar to that of RE (but actually working, unlike REs ability). This would give them the ability to fullfill the above stated tasks better, by keeping them interessting alongside cons and penals.
Show Spoiler

For those of you claimnig this will make them even more unattractive, take a look at OH shocktroopers and think again^^

I am completly fine with buffing the Churchill for better inf support, if it gets the heavy status as well. The main issue with the Chruchill (seen by a primary achsis player) is its numbers. The 'vet feed' might be an indirect advantage for the achsis, however the churchill gets vet as well due to damage and vet 3 stugs are completly useless if you are not able to finish your target before the stugs get wiped by your oponents superior airstrikes etc + a sniping firefly (or Su85/jackson in team games). My suggestion would be an increase in armor with a slightly HP decrease + buff its main gun (stats still worse than OH tiger but no price increase),so that the churchill performs as a good inf support platform in a (literal) Tank-role, while being limited to one model at the same time and so not overdominating due to its mere mass.

I would recommend it if all demo charges would be like the booby trap abillity of obers and jager. this still ensures a slowdown of enemy capping due to the lost models, but does not insta wipe units, thus is not a cheesy nobrainer option like e.g. the soviet one.

I my opinion it is quite map dependend and how you pull it off. As an early-early game unit at maps like semoski it is quite potent if you support it with RM. Additionally you force your opponent to react to it by investing in a raketen, thus weaken his/her AI and create more space for your RM to cap and/or create good fighting positions. However, the Panzerfaust will only be a threat if the OKW player teched up, and you want to stall this with the WC51 not counter the building. I get rid of the WC51 asap to get my fuel back and use the highground I achieved with it in the first 4-5 mins. For OH it is not viable because they have their Panzerfaust since min one + Mg42 thus creating a threat since the time you call the WC51 in.
Summed up: Do not rush it unsupported into FOW and combine it with RM/RE to hit as hard as you can in the first minutes to push back the first pushs and make use of the maps properties and it will give you a good start into the game.