The most recent Average Bank Financial Strength Ratings by Country produced by Moody's gives a good idea of where those long on cash might like to place deposits for a rainy day without landing up in an Icelandic debacle.
There are no countries with an average bank ratings (weighted by assets) at any of the top 3 grades (A, A-, B+), but there are 4 with the next rating (B), namely Canada, Singapore, Australia and Hong Kong. Although English is spoken in all these locations, the time zone may be inconvenient and the withholding taxes in all but Hong Kong might be unwelcome to some, while the "China risk" of Hong Kong might convince others to look for another home for their cash.
Dropping a grade to B-, we have Chile, a little out-of-sync timewise, but not so convenient for a friendly chat with the bank manager, even if you do speak Spanish. Closer to home, there are also the B- rated Norway, Sweden and Finland, all in approximately the right time zone, safe, free from withholding taxes on interest, but not renowned for their level of service to international clients, which leaves only 2 countries at this level of safety that tick all the other boxes: Liechtenstein and Switzerland.
For what it is worth, Britain's banks are rated 3 notches lower at C-; below Brazil and Jordan and on a par with Slovenia and Colombia.