Is your plan to play the arrangements you have made on the syntakt and then midi sync with a sampler that will play your sampled bass and guitar parts?
Are you also planning to use the sampler to sample the sounds from the syntakt and further effect/resample those sounds?
Does this setup need to be portable?
Do you envisage wanting a lot of channels to play with on the sampler, or would 7 or 8 suffice?
Edit: is the max sample length on the digitakt long enough for your guitar and bass parts? How long can samples be on a digitakt?