Ableton Live with Push would do exactly that… OR if you want hardware maybe the Akai Force could do the same thing and those can be found for a decent price… and sampler is already integrated… plus way too much more 
I have a Launchpad mini and a Launchcontrol XL, that enough and great for my use case. The Launchpad is enough as I don’t need velocity, and it’s tiny which I value on my table (real estate is my limit for gear, so, nice trick!). The Launchcontrol has fader which is great.
Push is too big and too capable for what I need to do. Force is also a complex machine, i’d rather have a hidden laptop with lid closed and deal only with my controllers.
But thanks for the suggestions, they would certainly work!
do you have an iphone or ipad?
yes
atom 2 is a sequencer AU app, will need a host to run it in but it has launchpad compatibility. not sure which launchpads it works with but definitely the new one. might be worth looking into, could use it to trigger not just samples but full midi sequences etc. its 50% off right now for £8.99 I believe.
Interesting. Still, I’ll stick with Live. Does time-stretching and clip launching, clip recording beautifully 
that is 100% the easiest way