Are there any bulbs for the tail and turnsignal that would be brighter than stock without going to LED or HID?I have the flat lenses on my 09 Ultra.

 

I don't think HID is an option for any rear lights, never heard of it anyway.
LED is probably the only other option you have for Stop/Tail/Turn lights on anything with the stock incandescent bulbs.

 

There are some aftermarket bulbs that are brighter but they are expensive and they don't have a very long life.
There are some superseded numbers in mini bulbs that are brighter I use 2357 bulbs in the front instead of 1157 because they are brighter, I believe there are newer bulbs for the rear lights but you would have to stop by your local auto parts store and look at there bulb catalog to find them, there are spec pages in rear of most bulb catalogs giving dimensions, styles and candlepower.