Depending on your requirements, you can save each Spark "song" as a Spark Project (that saves the Drum Kit, the Patterns and the Song aka "pattern playlists").
This allows the freedom of using different Drum Kits/Sounds per Song, if you need.
The only "issue" is that you need to load each Project at the beginning of each Song you're performing.
The other option is to use those 16 sub-songs (or pattern sub-playlists) as the building blocks for all your songs, if 8 patterns per "song" is enough.
If all you need is to perform 9 songs, then there's plenty of "room" in those 16 sub-songs to fit any longer than 8 pattern songs (because each sub-song can be chained to the next).
The issue here is that you'll be using the same Drum Kit throughout the live performance but with the advantage of not needing to do any additional Project loading.
A 3rd option is a mix of the above i.e. you could store your 9 song set performance on 2 or 3 Projects, only having to find a couple of seconds rest to load the next project in-between songs.
You'll have to do some planning (some tests) and some decisions on how best to use the Spark features.
I'm convinced that Spark is flexible (and powerful) enough to suit your needs, at least from what you described
Keep in mind that, Spark isn't an hardware drum sequencer! It's an hybrid i.e. an USB controller + software running on a PC/Mac and now also iPad.
I'm only saying this because you mentioned using an hardware solution and I've seen some users make a bit of a confusion, thinking SparkLE is *the* drum computer, which isn't.
The closest to that is an iPad+iSpark+SparkLE combo
