Wall Jumping (Limited)
While not as robust as in later Metroid games, Samus can perform a limited wall jump. If you jump against a wall and immediately press the opposite direction and jump again, you can gain a small boost. This is rarely required but can sometimes help reach slightly higher ledges without the Space Jump.
Bomb Jumping
In Morph Ball form, dropping a bomb and then jumping just as it explodes can propel Samus higher. Chaining multiple bombs can allow for significant vertical ascent, reaching areas otherwise inaccessible without the Spring Ball or Space Jump. This requires precise timing.
Screw Attack Movement
Once you have the Screw Attack, you can use it not just for combat but also for movement. It destroys certain blocks simply by touching them while spinning, opening up new paths or revealing hidden items without needing to use bombs or missiles.