I live in the neighboring town of Thousand Oaks, so my comments are colored by the fact that anyone from my town looks down on anyone and anything from Simi Valley.
Simi is pretty much a bedroom community, although they have done a good job of cultivating light manufacturing and office jobs over the years. It is low in crime. There is a blues festival in the spring. Green Acres market has the best tri-tip beef in the area. You can find any brand of chain restaurant your little heart desires. There is a mall. There are plenty of parks. There is a train station. The Ronald Reagan Library is on the edge of town. There are many multiplex theaters. There are two bowling alleys.
OTOH, it is very low on the funky vibe you may be familiar with in the PNW. The roads are straight, wide, and perpendicular. The houses vary all the way from beige to tan. I can't even think where one would go for live music. I think there is a civic auditorium, but it doesn't seem to book many interesting acts.
Cycling in town is not excellent, but is ok. They have tried, with limited success, to introduce bike lanes over the years. It's the sort of town that would just as soon not have to deal with the spandex set, but is much more attuned to equestrian needs. There is a trail along the Arroyo Simi, but it is configured such that every mile of so you have go up to street level, dismount, go through a turnstile, press the buttion and wait for the light to change.
It is a relatively short jaunt to the nice riding mentioned by chudak - maybe 10 uninteresting miles or so to Moorpark, another 10 very nice miles to Santa Paula, and another 15 or so very nice miles to Ojai. All of those towns have funkiness ranging from at least a little, to lots and lots.
HTH,
JSR