You can resize and move views (tree, dopesheet, graph, etc) around. Drag view edges to resize. Drag view tabs to move. You can drop views on top of another view to create tabs. You can't yet detach a view as a separate window, though you can resize the Spine window to cover multiple monitors.
Page up/down cycles through your selection history, reducing the need to re-select the same items. Selection groups can make your most common selections faster.
The does tend to require a lot of scrolling. I recommend arranging your tree so it's the full height of your monitor. The tree filter can help to reduce scrolling somewhat. For example, if you need a bone, hide everything that is not bones. You can also press enter, then type to jump to an item by name. Enter again to jump to the next match.
Generally it's better if you can avoid hunting through the tree to select an item. If you need a bone, you can often find it faster in the viewport. If you need a slot or attachment, sometimes it's faster to click am item in the viewport so that the tree scrolls near the item you actually want. The skins and animations views can spare you from hunting in the tree for those items. We plan to add a view for constraints and possibly show constraints in the tree under all the items they affect.
