Not only Buran was riding atop of self-capable Energiya and therefore didn't carry big engines. Buran was unmanned-first, which required quite a bit of ingenuit

Not only Buran was riding atop of self-capable Energiya and therefore didn't carry big engines. Buran was unmanned-first, which required quite a bit of ingenuity back in 1980-s. It had bigger payload than the Shuttle. One of better features of Buran was nontoxic propellants onboard. Buran's RCS were oxygen-kerosene, and LOX was stored onboard - liquid - for a month-long flight duration. That's something which Shuttle and today's SpaceX designs still lack; after Shuttle landing first order of importance is to get rid of remains of very toxic onboard propellants. Same for Dragon.