Trying to help a friend put together a Dexterity based character with battlefield control options. At the moment, the character is 7th level (Elf with the Winged template and 5 class levels). Uses a Kusari-Gama and Improved Trip, but is worried that the tactic will become ineffective as opponents grow in size and/or get Freedom of Movement (depending on how that interacts with making somebody prone). Since she can hopefully rebuild the character as necessary, the build shouldn't matter TOO much, but at the moment it's Swashbuckler 3/Fighter 1/X 1 (we just leveled, and so she hasn't picked the most recent level yet). Stats are Str 14, Dex 18, Con 14, Int 16, Wis 10, Cha 8 (or something thereabouts, anyway). She's expressed a disinterest in size-increasing abilities for thematic reasons, but is willing to consider them if it's absolutely necessary. Don't remember what feats she has other than those I've already mentioned and their prereqs (and weapon finesse, of course, being a swashbuckler). Any ideas at all would be helpful. Thank you.