A lot of times the Beastmistress(I like that term) can use her creatures to sort of slow you down but it's an imprecise tactic at best. She CAN slow people down to a degree but Teleport will always be a problem. Still if you can get a good groove with her she's devastating. Just hard to get that groove.
Yeah: I have a johktari spellbook, far from top level competitiveness, but I made it for use against an opponent I usually beat to get a closer match-up. It relies on her rather overpriced bow and rather overpriced dire wolves to try and get them bleeding as much as possible, and then dropping deathlock and attacking/running away.
The small creatures blocking is great. I love the bobcats: cheap, the charge means people don't want to move away from them, and the dodge means they can't rely on a strong creature swatting them with a single hit. Foxes being fast is obviously helpful too.
The plan for the opening is something like
Turn 1 - run into centre, cast enchantment ring. Drop Lair one step forward (2 mana left)
If opponent moved out of original space
Turn 2 - Lair summons bobcat, cast rouse beast and attack with it. Cast hawkeye f/d (6 mana left)
Turn 3 - Lair summons bobcat, cast bow, reveal hawkeye, shoot (0 mana left)
If opponent stayed in original space I'd just use a fox instead, and move my mage into the same space as the Lair.
The charge ability and reluctance to get hemmed in means people often stay in the same zone as the bobcat, which means I can shoot at them with impunity.
This wouldn't work against tournament spellbooks, at all. But in casual games, is very fun!