There are things you can do to make computers more suitable for this stuff but it gets expensive fast and less convenient quickly. Toughbooks are tempting, but expensive, rackmount computer can be managed for not much and keeps the computer safe in its rack but now you more and bigger stuff to haul. Taking a disposable approach with rpi or the like is tempting but not exactly ideal. Computers/tablets are great and have their uses but are not a replacement for hardware yet.
The big problem for me with all things touch screen is that they get confused by water on the screen, which is an issue when it is hot and you are sweating or on a stage with bright lights cooking you. Not an issue if you just want to tap out beats but a serious headache if you want to adjust parameters. Connectors on tablets are also an issue, USB is not a very secure connection and the wireless options are not great. Give me a tablet with a plastic screen, 1/4" ins/outs, can run PureData and will not get confused by water on the screen and I will probably give up my hardware.