I have a .com website hosted in the US. Most of my traffic comes from there, but I found better prices and service in a webhost with a server in another country. Will it matter if I make the switch, given that I have an international audience but traffic mostly coming from the US?
If you're targeting international audience, you can host your website wherever you want but if you're mainly targeting the US, the best practice is to host your website in the US (getting IP address of the server from the US).
Indeed, location of IP address of your server is taking into account for search engines and SEO. However, it's not a major factor and you can rank well in the US with a hosting service from an other country.