I sympathize with you. Apparently, StackExchange has recognized from the start that the new themes were going to lead to a sense of "missing identity" on various sites. Personally, I would have preferred they give us a longer beta-testing period so that we could address these problems before they went live, because a sense of "missing identity" is a big problem for community-based site.
But StackExchange apparently has strong internal reasons for going with this new system -- there were too many site-specific features and it was becoming unmanageable for them to maintain the site. Things are not going back to the way they were.
The silver lining is that we do have customization options available to us, and we have the power to ask for more even if they're not currently available. I think it's well within our power to rectify the situation with some creative thinking. I've opened another meta question to discuss some of these options. I'd encourage you to join me in channeling your frustration into contributing to the conversation on that thread or to ask your own meta questions to discuss these options. MO is too important to me to see the conversation end in despair like this.