You may despise large cities but the larger agencies have the most variety of possible assignments. Those assignments are often permanent as well, so you could be a detective or motor or whatever for the majority of your career. Smaller agencies tend to have rotating special assignments (i.e. 4 years then you have to go back to patrol).
To put size in perspective, Armed 24-7, mentioned large OC agencies. Pre-budget cut sworn levels were around 400 for Santa Ana and Anaheim, 200 for Huntington Beach then around 150 for Newport Beach, Costa Mesa, Fullerton, Garden Grove and Orange. Where as SDPD is around 2,000, LAPD 9,000, OCSD about 1,500 and LASD runs around 10,000. Keep in mind as well, if you work OCSD in a contract city, you get the opportunities associated with the larger department but can probably spend your post-custody career in the same 'small city' (60 person agency) if you choose.