I've seen someone on YouTube who added a Matty Wand and the Matty sound card thing to the inbuilt speaker and it sounded alright. I think it could be made a bit louder than it is by default maybe?
I've modded mine quite a bit. I switched the straps out for some ALICE Straps (although I've not managed to mount it to a frame yet. Those things are crazy expensive here in the UK), I then did some weathering to it making it look beat up, added some extra stickers, and then I added the proper running cyclotron and power cell lights, and then I went a bit crazy. I decided I wanted to add the slime blower attachment from Ghostbusters TVG. I'm very happy with how it turned out though. There's a thread on here showing what I did if you search for it.
I'm short with small hands too but yeah that thing is definitely tiny. I'm going to switch it out for a bigger wand down the line I'm just not sure which kit to get yet. I also want to improve the mods on the wand. I've added a 20watt Blue tooth speaker inside it too so it plays music from my phone nice and loud.
This is my pack so far. I came second out of 50 at a recent cosplay contest so I was very happy with that!