The screenshots look all fairly similar (and apparently all good) with sparse bullet patterns, a forward-only weapon, medium intensity dodging and a moderately crowded amount of enemies. So, in order to make an interesting tutorial, take care to include interesting features:
- colorful sprites (unlike 01 and 10). Maybe a somewhat higher resolution would be more suitable,
- tiled backgrounds (07 and 08 have the most complex ones)
- complex lasers with repeated sections (06) and decorations at the base and head (02, 03, 04, also 09 but it looks too simple); all Dodonpachi games contain magnificently phallic examples
- if not considered too complex, bending lasers (Raiden, Gunhed...)
- dumbfire projectiles (if at all possible, not only forward)
- aimed projectiles
- self-guiding projectiles
- collectible items
- varied scrolling rates and directions, and more generally camera movements (including zooming)
- complex and controlled enemy formations (both spawning and movement)
Make a plain, mainstream game instead of pursuing fancy mechanics: a tutorial should be concerned with common and/or basic techniques that are going to be almost always relevant, not with extreme and specialized ones.
Good luck!