Basically, all u need to look out for is the material and a tailor who is updated about trends as i realised most peninsula tailors share the same seamtresses. Design wise, u'll just need to tell them what u want n they'll tell u with their experience whether it is feasible. If u r looking for good workmanship, head to thailand, HK or shanghai. I have not tried personality menshop but i've tried tessuti (dunno how to spell), dezenno n frank tailor. Frank's alterations r good but i have never tailored any shirts from him so i cannot comment on his materials n such. As for tessuti n dezenno, their material r funkier n more high end. I especially like dezenno's wool pants.
Psss...Avoid dreamland tailor unless u have $$ to spend. The aunt boss is damn snobby and a few friends of mine had a taste of her snobbishness as well so i guess i'm not sensitive. Hope my information helps.