killihu has released Control Matrix for Ableton Live.
Control Matrix allows you to modify parameters of different tracks/devices in the same floating window without taking exclusive control of them. In addition to offering the convenience of having all parameters in one window, you can save up to 6 presets for A/B style comparisons.
Control Matrix has 3 different window sizes, displaying 8, 16 or 32 parameters. If you need to control more parameters you can always load more instances of the device.
Price: 9€.