I was wandering if you are planning to implement pre-processing/visualization tools for high density EEG data eg. adding a scrolling bar and other tricks to navigate through 'column' data more easily. It would be a great advantages for EEG users working with 128/256 channels!
You have zoom tools available on the right side of the time series figure. Look at the tooltips of these buttons to get the mouse and keyboard shortcuts.
The Brainstorm viewer was designed to review MEG recordings with 300 simultaneous signals sampled up to 20kHz, so you should be able to configure the environment in a way that works for you. We offer predefined sensor selections for various MEG systems, but not for EEG (yet).
Please let us know if there are display configurations that you think are missing and that you don't manage to achieve with the montage editor. (include screen captures)
If you create montages based on the 10-10 nomenclature that you think can help other users, please export them and share them here, we could maybe integrate them in the Brainstorm distribution.