a tank should be 2nd tier in damage... its the trade off you have for being a tank, having sustain, cc etc
i dont think you are understanding how you are suppose to clear jungle and or farm
even in lane you have to auto to farm. it helps
i personally i have 5 rune pages for him alone ( i can use for a few other champs)
the one i use the most currently is a mixture of ad /as reds, flat hp seals, 2 armor quints 1 cdr quint. and cdr blues
i get +3.8 ad rounded to 4 , +8.5% attack speed rounded to 9%, 8.5 armor rounded to 9, 72 hp lvl 1, and 10% cdr
you take that with 5 points in attack speed mastery and you take natural talent gives you more as/ad from there you build tank...
tanks have high base damages therefore really dont need AP/Magic pen in order to do damage
if you care to do damage as maokai as jungle you can run flat attack speed reds, 3 ap quints, 9 armor seals and whatever blues you want... mr vs heavy ap teams. cdr, ap per lvl etc
a build of
while taking 72hp boost the passive hp you get... then you pair that with
giving you more magic damage including more aoe magic damage from
plus more bonus hp , cdr, mana, hp, the catalyst passive that heals you when you use a spell and gives you mana when you take damage from enemy and it helps your APC or other magic damage on team do more damage too...
and if you really need more AP as a jungle such as maokai considering all of his abilities are cc/slows
does wonders cuz of magic pen, hp, ap and the dot passive % damage which all synergies with
and the rune /master set up you take... if you dont want to take the extra attack speed with masteries take sorcery for 2% more damage on spells which will help your over all damage as well