A California S Corp pays a 1.5% franchise tax on income with an $800 minimum. There is no income level at which the S Corp franchise tax is less than the combination of the LLC tax of $800 + the income-dependent LLC fee.
http://www.nolo.com/legal-encyclopedia/california-state-busi...
There's also a requirement to register with the state if you're an LLC incorporated in another state and will be doing business in Illinois. $500 filing fee and you have to have a registered agent within the state. The relevant law is http://law.onecle.com/illinois/805ilcs180/45-5.html, but it's not entirely clear to me what "transacting business" really means. The seemingly obvious meaning would imply that every little LLC selling anything would be required to spend $500 once plus annual fees to a registered agent before selling to anyone in Illinois.