In my opinion NATO would definitely withstand all the difficulties faced the high cost of expansion. Lets face the fact NATO has been round since 1949 and its seems to be all the nations involved are supporting NATO movement. I don't think that finance would effect NATO because they have lots of support. And the biggest fact is that it is beneficial movement that has a positive impact.
No, NATO would not withstand the difficulties faced by the high cost of expansion, because expanding NATO would only make it less effective. The operations of NATO would only make it more like the United Nations. Of course, the United States pays more towards the United Nations than anyone else. The same would be true of NATO.