I like to feed mine a small feed of grass chaff, a sprinkle of oats and a handful of high fibre cubes during the warmer months just as a carrier for their supplement. When the grass stops growing they get bigger feeds twice a day (with the supplement) and ad lib forage.
I avoid alfalfa because one gets itchy on it, although the other is fine.
Neither of mine can have any molasses sends them nuts and they both hold there weight well so they have a basic diet of hay and grass, pink mash grass chaff and micronised linseed.
I find they don't really need high energy feeds it just makes mine silly to ride, they have enough natural energy for what I do really which is just hacking and schooling.
One of mine is hard to keep weight on and reacts to lots of Alfalfa so he gets grass chaff, ERS pellets and speedi beet with a balancer, the others get varying amounts of alfalfa a oil, speedibeet and a balancer until they are in hard work where they get Saracen releve or ulca kind nuts