I wouldn't get too concerned for a first trip. Use what you have that you think will work and make mental notes of likes/dislikes and imagine what might work better for you if you plan to do it again. Traction on wet logs and slippery rocks, something with a hard sole that protects your feet from pokey sticks and sharp rocks, something you can swim in and something comfortable to you is a plus. The lighter, smaller profile the better.

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But remember, people like everything from flip-flops to the big clod-hopper type Frankenstein boots yet it's not terribly unusual to see a barefoot footprint in portage mud come August.

Air and water can be cold in May so GoreTex socks are nice if they fit well inside your footwear and tight to the calf in their upright and locked position.

A few days of continually wet feet isn't much fun (especially in May) so an extra dry pair of shoes/boots/whatever for camp is always welcome. Boots are half of a two part system and the right type of sock plays a big role as far as comfort goes. A lot depends on conditions, tolerance and expectations.