[gnodar]

I would take some Electrical Engineering classes, maybe even minor in it. Given an abundance of time, I would also take some higher level math classes. Based on your interests a broader exposure to these fields, which are strongly related to CS but only lightly-to-moderately covered in a standard CS curriculum, can only help.

For me personally, I would do a deep dive on distributed architecture, which you may also be interested in given your interest in p2p.

[mehrdadn]

When you say EE, do you mean signals/optimization/control/etc. or do you mean circuits/device physics/RF/etc.?