Hey, here are a few suggestions for expanding the British tech tree flavour (Thus adding a bit more)

Light Armour:
FV301 (FV304 SPG and FV305 TD)
FV401 (FV404 SPG and FV405 TD)
Scorpion
Scimitar

MBT
Centurion Mk 7/2 (Conway TD)
Chieftain (Chieftain Sabre SPAAG)
Cheiftain Mk X ('JagdChieftain' TD)
Challenger I

Super Heavy
Conqueror (FV215b TD, Conqueror Gun Carrier Experiment SPG, This is not strictly a Super Heavy but we didn't really invest in that by then)

Anti Tank
QF 32 Pdr (This did exist in a mobile infantry division but only saw testing)
BAT Recoiless Rifle
WOMBAT Recoiless Rifle

Infantry Anti Tank
MOBAT Recoiless Rifle

Modern Anti Air
Green Mace

Jet Fighter
English Electric Lightning
♥♥♥ Sabre (More suitable for Canada, Australia and New Zealand)
de Havilland Venom

Sea Jet Fighter
de Havilland Sea Venom
de Havilland Sea Vampire
Sea Meteor

Jet Bomber
Bucaneer (Strictly a Sea based naval bomber but later used by RAF)

Mechanised
FV300
Warrior

This is all I can think of off the top of my head that are around the timeline.