Simple MIDI editor recommendation

I want to create some sounds for the game, me making plopping, popping and puffing noises at Audacity is only getting me so far.

Unfortunately I have no experience at all generating procedural sounds. Is there some nice, beginner friendly editor somewhere where I can try the different settings and get actual values I need to plug into the PlayDate SDK?

me making plopping, popping and puffing noises at Audacity is only getting me so far.

Since you’re using Audacity, you could try heavy use of various effects — starting with filters to cut out parts of the spectrum so they sound less like the human voice, then adding other effects. You can also use the tools in the Generate menu to start with a non-voice signal and process it — use the “Fade” effects to add envelope.

Simple MIDI editor … beginner friendly editor somewhere where I can try the different settings

If you’re looking to make sound effects, MIDI is probably not the way to do it. MIDI is best for defining music (i.e. notes with different pitches over time) given that you already have an instrument (samples or synth).

But for something simple to make sound effects, check out jsfxr. It can give you a sound with random parameters and let you tweak it into something you like. If you’re looking specifically for sounds that can be procedurally generated by your game, rather than to make a fixed sound file your game loads, it still might be a useful toy to explore how to synthesize sounds using oscillators, filters, and envelopes.

That's a good idea. I didn't think about using Audacity directly.

jsfxr looks interesting. I was thinking of figuring stuff out making a PlayDate specific synth emulator on a web page.

Have you heard of pico 8? It's a fantasy console (pretend old console) that has a full suite for making games. It has a very simple sfx/music maker with a handful of instruments and effects. You can even just draw the shape of sounds on a graph. You can then export them as wav files to port over to playdate.
It can only make retro style sfx and it is very limited, but it's a nice user interface and is easy to experiment with so might be what close to what you're looking for.

I haven't. I'll look, thanks.