A union calls the plans "ill-thought out", but management says change is needed due to rising costs.
The Sussex and Brighton Strategic Authority will meet for the first time on Wednesday.
The project in Hove's Knoll Park is "for young people to have a safe, welcoming space", says charity.
Brighton & Hove City Council says it does not have enough funding to "fix everything".
Brighton & Hove City Council is planning to tear down and rebuild the King Alfred Leisure Centre.
Services at the Wellbeing Hub at Preston Park could be cut from five days to just six hours a week.
The council looks at changing the rules on how long roadside memorials remain in place in Brighton.
Ministers are considering a proposal to expand Brighton into East Sussex and to split West Sussex.
A report to councillors in Brighton says new rules are "to ensure greater clarity going forward".
