i made a list of themes here:
http://forum.kiddieparty.ph/very-important-party-vip-tips-f6/character-themes-t42.htm
common talaga sa girl ang disney princess. meron ding dora, barbie or hello kitty. kung gusto mo ng puwedeng boy/girl, puwede din ang winnie the pooh, sesame street, care bears, or precious moments.
for the souvenir, depende siguro sa budget mo.