Turning the heat up and increasing the oxygen is pretty effective and adding some salt also helps although plants are not such big fans of either of those things. A quarantine tank is a good thing to have since it is far cheaper to treat a small tank than a large one, and it helps to put new livestock in there for observation before adding to your big tank.
Local fish stores used to routinely quarantine their new stock and you would see many tanks that were dark or had "hold" written on them but sadly that seems to be a thing of the past and often I see fish being sold that were just unpacked from the shipper hours or even minutes earlier.
Having a hospital tank can certainly make life less stressful and does not take a lot of extra effort. Just keep a fish or 2 in there to keep the bacteria established.
Having a hospital or quarantine tank is always a great idea. But once you see ich on a fish in a tank then that whole tank essentially has ich. This is why you should be very careful when buying fish from any store that uses a centralized filter system. One filter system feeding various tanks means that if you see ich on only one fish in one tank there is a strong possibility that any and ever fish within that system can carry ich back into your tank at home.
I picked up a few more rummy nose from the LFS the other day and since the guys were all active and swimming I didnt notice they had ich until they were in my tank for about 2 days. I'm ramping my heat up to the 88-90 degree mark in an effort to combat that now. I've honestly never tried the heat treatment before and have had luck with products intended to treat/kill ich but decided to try this approach first this time.