Super Metroid is interesting in that it is linear in some places and non-linear in other places, providing the player a fair bit of freedom in how to work through the game. I know some items are certainly required, such as the power bombs and the dash boots, yet certainly not all of the missile packs or bomb packs are required. That said, are any of the other items so necessary that the game simply cannot be completed without them?
The X-ray Visor, Spring Ball, Spazer and Plasma Beam are all not needed to beat the game if memory serves me.
The Spring Ball is just really convenient in a few places, the X-Ray is not needed to solve any puzzle if you already know the route and the plasma beam can be skipped if you invest in enough missiles (and avoid the few enemies that are only vulnerable to it).
Back in the day I have done something around 2 hour run (no tools) at 100% items, so it is quite possible to move through the game and fast and complete too.
If you are going for the minimalist, you should skip the Spazer and go for plasma, as it can damage some bosses when charged.
There are a few items that are totally optional: X-Ray visor, spring ball, spazer, and plasma beam. Even through a totally normal playthrough these can be skipped
However, if you play the game in a different order than intended, and use some advanced techniques, it is possible to beat the game with far fewer items than that. These are the minimum items needed without using major glitches (Super Metroid 14-15% Walkthrough)
- Morphing Ball
- Charge Beam
- Speed Boots OR Ice Beam
- Varia Suit
- Gravity Suit
- Energy Tanks (3)
- Missiles (1-2)
- Super Missiles (2-3)
- Power Bombs (1)
It is also possible with other combinations to skip other items. For instance, it is possible to play through with neither the Varia suit nor the Gravity suit, but you need more total items to do that (Reverse Boss Order/Suitless Walkthrough). And the charge beam is not necessary if you have other weapons.