WeaserP:
Yes, I did see the FAQ but I assumed that was if you had no other balls in your "bag". My thought is that it would be nice if the selection went to the next "better" ball descending down to the Basic ball or at least gave you a choice to choose from your available options (certainly not to stop the game and buy any).
Not a big deal if everyone is held to the same rule but just a thought (if any programmers were listening in). Thanks.
There's no "would be nice" because the CEO declined that auto-selection option a year ago. (I know that it's their advantage, so why expect a change anyway?)
There's no players' choice in competitive games here - they are not going to start it on this plea.
But, you may well visit the Pro Shop during the game (multiple windows allow for multiple allocations) and buy further balls of the type which is installed - they will be available in your game as long as you are still playing that type.
This will only be necessary if you miss the alert to buy more when the "last ball in action" situation looms at the beginning of or at any moment through the game.