Snapedom

I agree with much here. Esp. regarding Lily's immediate response being to reassure Severus that she doesn't like his rival. :)

A few quick thoughts to add:

I personally don't see Lily as thinking Severus is timid, since he studies the daring Dark Arts and is ballsy enough to fight back against The Marauders. And who knows what kind of spell or potion experiments she's been privy too (nothing Dark, I imagine, but experiments do have a way of going wrong until gotten right).

Also, Lily may not value reckless thrill seeking like James or Sirius. She may merely value the virtue of bravery, and might think that being brave to the point of foolhardy, is dumb. Not that I don't think she has a more adventurous streak than Severus...I just tend to think she has less of one than James or Sirius. Again, I give benefit of doubt. So, that might be part of why she would scold Severus for foolish risk taking...not because he was not as 'good' at risk taking as James, but because that kind of risk is foolish to begin with. Whereas risking one's life to save someone (like James did in this case), would be a worthy cause for life endangerment.

I see James and Sirius as the type who might like to 'play chicken' on motorbikes (crazy risky adrenalin rush), Lily as the type that would go whitewater rafting (thrilling and risky in a more reasonable way), and Severus as the type that would prefer wild roller coasters (all the thrill with very little real risk).

I do think that Severus thinks that Lily sees James as more 'competent' on the risk taking side of things, though. Or he worries she does.