Two water bottles/cages and a saddle (seat bag) for tools/phone, etc are my preference. Two large bottles is good for 50-60 miles, on hot days there is always a place to stop and refill. I have a Camelbak I use for kayaking but don't like that sweaty back feeling, or any weight up high on my body.
I don't wear jerseys either, so the saddle bag is where I can carry flat repair stuff and my phone.