I like
Thomas. It reminds me of one of my very favorites,
William: classic and comfortable but still attractive and not boring. I like
Tom well enough as a nickname, though I'm not a huge fan of
Tommy.
I think
Tomek is kind of cute, though until I searched the database for names related to
Thomas I had no idea it was even a name. There aren't many variants of
Thomas that I just outright dislike, with the exception of
Thomasina. Bleh. I like
Tomasa or Thomasa and would probably get used to Thomasine, but I hardly ever like -ina endings.