The 53's ARE Sea Stallions, at least the CH-53D. THe CH-53E is called the Super Stallion and has three engines and seven main rotor blades vs the two engines and six main baldes of the CH-53D.
"Cramped"? Relative to what, a C-130, C-17 or C-5? The 53 cargo compartment, IIRC, is 25 feet long, 6.5 ft high and 7.5 ft wide. It has been 40 years since I last flew one, so my numbers may be a bit off. But I do remember carrying a jeep & trailer inside one.
I've also flown "Frogs", the CH-46. All Helos are "a group of spare parts flying in loose formation", a "mass of machinery which has been forced into the air against its will".
A lot of mechanical parts to break - far more than in a comparable fixed-wing aircraft. The main rotor mast on the CH-53D was subject to 300,000 lb-ft of torque. The centrifugal load on each rotor blade was 100,000 lbs.
Almost everything you ever wanted to know about the various Sikorsky H-53 models
