"More Peroxide?"Hard to say, I would but that is me, but at minimum, take a wet q-tip and rub over the wet coin and see how much crud comes off yet without taking off any loose corroded patina. If a lot comes off onto the q-tip, then I would do another peroxide soaking and after it is as clean as you are brave enough to do, put it in distilled water or if none at least boiled and then cooled a bit tap water to help neutralize the acids. Dry thoroughly, then I would coat with a hot bees wax or Renaissance Wax if you have it, but Bees wax is readily available and cheap and it works. I melt the wax under a lamp and with the coin on a plastic lid, it covers the coin, flip it over, ensure the edges are covered, once completely covered in melted wax, remove, wipe of excess, let dry then buff with an old toothbrush. This works great on old coppers that need some sprucing up.
Don