The current experience when running in a disposable mode is quite poor, mostly due to a very long setup time needed to download and install all dependencies. I see two ways how to solve it:
a) depend solely on custom images which already have all the needed packages pre-installed
b) trim the dependency chain as much as we can to shorter the setup time

We might end up going with a), but it is somewhat inflexible and it would definitely be a contentious topic. Going with b) can help us regardless of the path we take (even if we bake it in the image, the image will be smaller with fewer deps) and even in some bonus situations (ssh mode?). So I think we should try it.

This is most probably related to #587. We need to modularize libtaskotron in such a way that we can avoid installing heavy-weight packages (like testcloud) when we don't need them (i.e. on a disposable client). That will considerably shrink the download size and time. Try to find a solution for this. Even if it is not full modularization (as described in #587), concentrate at least on deps/modules which make the most impact for disposable client setup time.