If you dont want to create debris, and are going to a low orbit, (<100km) a probe core, and maybe a battery or solar panel, if you are going to leave it for more than a few minutes, and 40 RCS fuel on Rockomax 64 tanks can deorbit, allowing you to send asparagus staged rockets up. If you dont like the thought of having to control stuff other than your main rocket, asparagus stage is still the way to go for cargo, just make sure to dump the last stages with your periapsis under 10,000 meters, this will ensure that those stages are destroyed in Kerbins atmosphere. SSTOs do not lift a large amount of weight, relative to their size, and I find them best for crew delivery and return, as opposed to sending stuff like fuel or station modules up.