Regarding style and being a man.
1. Men don`t like in general to wear "floral" type of designs of any form.
2. Bold forms / Hard surface thing of modelling (think abstract organic /inorganic)
3. Anything that does not fit a woman to wear
Cufflinks , Pendants , Brooch ,Rings , Tie Pins , Cuffs (rare) are the main jewelry that any man can wear.
Topics can go from : Hip-Hop culture / Rock Culture / Custom motorcycle culture /Cars
Subculture related things and "muerte" type of designs : skulls , bones , and stuff.
Good way it is to ask some of your friends about what they like and what will want to wear : for pendants <- the most personal jewelry
Here a search I did not do before this thread
http://shpws.me/vrZM new stuff
I personally like floral design , but not to wear them ...looks good on women.
Still scratching my head to make a cuff for myself ...