Oh I have no problem with light RPG. Heck, I am even willing to call Diablo, Dungeon Siege and other clones as light RPGs
When I come home from work, I am usually already tired and my brain needs rest. So, in order to relax I play videogames (in addition to having some time with my family, of course).
When I am having rough weeks, I do not want to play games that require me to think much. Hence, light RPGs and/or other casual games are much welcomed in that situation. Even then I usually also consult walkthroughs 'cause I really do not want to think much while playing. During those weeks I want to be relaxed, not challenged. During those weeks, even games with too easy gameplay are welcomed. Let me give you an example:
Harbinger. This Diablo-clone-in-space gets bad reviews everywhere. The gameplay is way too easy, consisting only of hits and runs. RPG stats there are way too simple. Not much story either. But in the end I found myself enjoying the game. Why? Because I played it during rough weeks, and in fact that too simple gameplay helped me relax.
On the other hand, when I am having easy weeks, challenges are fine (Although I also draw a line between challenge and frustrating gameplay). During these weeks, more in-depth RPGs are welcomed. If you use Bioware games as standard for in-depths RPGs, then I cite KotOR 1 as a Bioware game that I have played.
That being said, no matter what week it is, no matter how rough or easy a particular week is, I do not enjoy RPGs that are way too complicated (for my taste). Take for example: Icewind Dale II. The D&D Third Edition ruleset implemented there is superb, but is also too much for me. I remember spending almost an hour and a half just for the party creation. So as much as I want to play that game in the end I never really got to play it. Maybe it is just me
but I prefer videogames that are not too complex to play. Maybe that is why I also do not play strategy games either.