DST Werebeaver's stats
150 health
200 sanity with -90/m insanity tick
27.2 damage, 44.2 damage to trees.
Night vision
240 insulation from heat & cold.
70% waterproof
25% armor
x1.1 speed
His beaver form seems great on paper. However, he can't heal himself, his crazy insanity tick and being unable to craft/interact makes him extremely vulnerable to everything, especially to rain and weather. His werebeaver can't even handle tree guards or birchnut trees well. Tree guards have too much health to be killed before getting overwhelmed by shadow creatures, and birchnutters have 50 health.
Basically his werebeaver form is high risk with a low return. Only choice is to chop trees fast enough or consume bunch of wood to regain his normal form.
If this was intended, a way to improve Woodie is probably to make it into a high risk and at least a medium return. This can be done by buffing his werebeaver's base damage to 34 and maybe 27.2 to players if pvp is turned on (idk, I've never played pvp). His damage to trees will be 51, enough to one shot birchnutters. His higher base damage would mean that he'll get less overwhelmed by shadow creatures, if you know how to kite them properly.