I played Sweet Home for the first time last year and absolutely loved it. It’s one of my favourite NES games now. I would highly recommend not using a walkthrough and creating your own map. Once you get a handle on the battle system, it’s not particularly difficult, and the backtracking / puzzle solving will mean enough experience so that you’re not having to grind.
My thoughts on the game are in our first Spooktacular thread for anyone interested: