A quick glance at the LaTeX book shows a wide assortment of arrows, dots, and miscellaneous mathematical symbols. Starting with v2.2, all of these have been implemented in latex.tcl. See the Arrows, Dots, and Symbols submenus for exhaustive lists of available commands.
NOTE: There are two Arrows menus. While one is down, press a modifier key (such as <OPT>) to see the alternate menu.