Save As JPG or TIFF - Stop showing Options

Those save settings are 'sticky'. That's the smart solution.

It's an extra step that I don't need.

Sorry, but creating such 'presets' in your preferences would be considered as unneeded by most Elements users; it's very important to verify the settings, especially if they are often changed depending on your output preferences.

I always want to save my JPG files at maximum quality.

It's your choice.As far as I know, most users use a setting like 10 instead of 12: the file size is much smaller and you can't see the difference. If you want maximum quality and the ability to re-process your image many times, use psd or tiff formats. Or open those jpegs in ACR to take advantage on the non-destructive parametric editing.