Frankly, I wouldn’t touch DJ-Tech with a 10-feet pole. It’s what I call christmas tree brand. It’s so cheap you can buy stuff there for your young kids for a christmas present. Definitely not something I’d want hanging on to the back of my 800 bucks controller.
More serious alternatives would be the Mackie Freeplay (also NAMM 2015 news), but you’d need two and two stands, which is suboptimal if you want to carry that stuff out to the street I imagine.
One of my favorite portable stereo speakers is the Roland BA-330. Great sound (don’t expect pounding bass from it, but then again, no serious battery-powered kit will give you that for any length of time) and runs like forever on a set of 8 (I think) penlite. Buy two sets of rechargeables and an extra holder and you can swap it out in 30 seconds flat and never have to buy batteries again.
You forgot to mention if you want 2 or 4 channels. But there is a lot to choose from. For outdoor use the way you describe it, it might be handy if you can keep your laptop to the side. The Numark NV is a serious option. At the top end of your budget, but seems to have it all. 8 pads, 4-channel, touch sensitive mixer part (not sure if the FX buttons are touch sensitive too though), jogs, USB-powered. Other alternatives are the DDJ-SR, the Reloop Beatmix 2 and 4 and even something on the low end like the Mixtrack Pro 2 would potentially tick most of your boxes (althoug I think only the Numark has touch sensitive anything).
.
