first of all, i have to say that Tixati is looking like a very capable P2P client - wow!

would be more trustworthy if the source code were at least available for review :)

things i've noticed...

* would be nice to R-click on the list column headers to configure the available headers (verses the way it's currently done)
* when adding bandwidth presets, it would be nice to input the bandwidth cap rather than having to adjust the current in-use limits
* option to hide (minimize to tray) the UI on Esc key press
* single click on the tray icon toggles UI visibility (instead of only showing it)
* add 'seeds/peers' column for transfers
* possibly split options into 'basic' and 'advanced' settings, with the latter being hidden by default
* maybe some UI polishing

all in all, i like it allot and i think the dev(s) and contributors!