Archers GMing Spear is something I thought long and hard about, and I ultimately decided that they were too much of a spellcasting class to be grandmastering any weapon besides the bow. Aside from that, the Ranger and Knight both can already GM the Spear, and the Archer gets enough of a defensive bonus from the GM Chain.GM Dodging for a Thief (or any other class besides the Monk, for that matter) is something I deliberately avoided, because you need a high Unarmed skill to make it work.
And it would really only make sense that a Monk could use the Meditation skill... but given their fighting-oriented class, it wouldn't make sense-game-wise. I might go back and allow basic Meditation for the Monk, just for ****s and giggles (well, that and it might be a good call in conjunction with Etheric's Staff).