Sure, most solutions to this problem will involve compromises and won't be perfect, but just about anything would be an improvement over the current situation.
Yeah, good point. Considering that I have to go back to the front page and I lose the "older" page 2 results anyway, it'd be far preferable to just send me to a newer page 2. Could likely pretty easily implement that with a fallback query param, so the link could be something like "?fnid=foo&startitem=31" or whatever. If the fnid is no longer valid, fall back to the startitem param.
Sure, most solutions to this problem will involve compromises and won't be perfect, but just about anything would be an improvement over the current situation.