Believe it or not, Metroid: Samus Returns actually features nine different ending screen variations. Each one is based upon what Mode Difficulty you complete and how quickly you completed it; the number of items you collects plays no factor at all whatsoever. Each variation will see Samus with a different appearance and pose.
Different End Screen Variations
Normal Mode (8+ Hours): Gravity Suit
Normal Mode (4-8 Hours): Gravity Suit, w/o Helmet
Normal Mode (< 4 Hours): Zero Suit Samus
Hard Mode (8+ Hours): Gravity Suit, Alternate Pose
Hard Mode (4-8 Hours): Gravity Suit, w/o Helmet, Green Hair
Hard Mode (< 4 Hours): Justin Bailey Samus
Fusion Mode (8+ Hours): Fusion Suit
Fusion Mode (4-8 Hours): Fusion Suit, w/o Helmet
Fusion Mode (< 4 Hours): Metroid Fusion Suit