My advice if you’re at the beginning of the hardware musicmaking journey: start with ONE self contained box that gives you enough tools to write music. The M:S is cool, and with sample locks, you can get a lot out of 6 tracks, but the controls are quite limited (no attack on the amp env, no filter env AT ALL…), which means that certain types of sounds will be impossible to make without using a computer beforehand to generate them… plus, polyphony will be out of reach unless you sacrifice half of the tracks.
Get something that gives you a bit of sequencing, a bit of drums or sampling, a bit of synthesis, a bit of polyphony. Circuit comes to mind, but you have to use a computer to load your samples and get deeper with the synth engines. Electribe2 might be cool as well: fairly editable drums, simple but onboard synthesis, usable effects, but the sequencing is less deep than with an Elektron unit. For a bit more money, you could get an op-z which is also a cool all rounder. There are also some cool, older grooveboxes that you can get for almost nothing these days.
In short: get a cheap, simple box that lets you do a bit of everything without putting you in a deadend too quickly… and see if you like it.