Before you do anything else, ask the front desk about rafting operators. Dont just book the first thing that shows up online - staff know which companies are currently running, which have the best safety reputation and sometimes can help you get a better rate than cold booking. Rafting the Cagayan is genuinely the must-do activity in CDO and worth prioritizing even if youre only here for 2 days.
Skip the mall food courts and walk a few blocks from the hotel instead. CDO has really good street level food - bulalo, kare-kare, fresh seafood, grilled everything - and its significantly cheaper and better than anything in a shopping center. Ask the staff for a specific place name rather than just a general direction, they usually have a personal spot they actually eat at themselves!
If Camiguin is on your list try to go on a weekday. The island is small and gets genuinley crowded on philippine long weekends and holidays. Leaving CDO on a tuesday morning gives you the whole place almost to yourself which is a totaly different experience than a packed saturday.
Ferry tickets back from Camiguin during holy week and christmas fill up fast, dont assume you can just show up and get on. Being stuck on the island an extra day sounds romantic until you have a flight to catch. Hotel staff can check current schedules and advise whether you need to book in advance for your specific dates.
Light sleepers should ask for a higher floor room at check in - street level and second floor rooms get the full CDO soundtrack all night. The city genuinely doesnt quiet down much, thats just what it is. Higher floors make a real noticeable difference and its worth asking specifically rather than just taking whatever room they assign you.