I'm playing with all characters every once in a while, and I have almost all of them (except Wesker) at level 100 by now. It's been a while since the last time I played, but I usually take on the daily missions whenever they're available, the others (Weekend Survivor, Large Creatures, etc.) not so much, only when I'm in the mood.
I also love to create specific unique themes for the individual characters and choose specific weapons and skills to match. For example, Alex is the "Wicked Witch", and her magic powers include telekinesis (Shockwave), summoning fire (Firebomb Bottle), mind control (Bewilder) and similar active and passive abilities that remind me of witchcraft. Barry is my "Ouch Maker", combining the strongest guns (Bushido with electric ammo, AMR, etc.) with the skills that hurt the most (Samurai Sword, Gesticulating, Crouch Power, Rocket Launcher, etc.), which makes him my best bet to cause as much damage as possible, whereas my Chris is best at taking damage (Coat of Armor, Shield, Magic Pixel, regenerative abilities), and Ghost Lady Jill avoids it altogether (all evading skills + active skills that distract the enemies' attention away from her). Etc...
It's just great how much freedom you have in creating your very own experience in this version of Rape Mode.