Going caramel would only require you to slightly break your base.. Wouldn't need to leave the bleach on long so it wont dry you out too bad. If you highlight, request an oil based bleach, as it keeps your hair moist during processing
Something to keep in mind when you go to get your highlights is the fact that they are likely to get lighter especially during these sunny summer months when you tend to spend more time outdoors (and in the sun). Your stylist can always tone them if necessary though.
and ended up doing a rich auburn brown with caramel highlights and i really love it! i decided to highlight gradually so it wouldnt be such a drastic change and i will be adding more highlights in a couple of months