<p>That seems reasonable, but it is beyond our control; it would have to be adopted by the developers.  You could ask on <a href="https://meta.stackexchange.com/">meta.SE</a> (but also note that they keep tabs on site metas to stay aware of requests like this).  </p>

<p>Note however, that you can always add a bounty after the existing bounty has expired / been awarded.  The rules are that you may be required to add a bounty twice as large as the first (<a href="https://stats.stackexchange.com/help/bounty">source</a>).  This may have a greater effect of attracting more attention to the thread though, in that it would reside on the featured list for twice as long in addition to the higher bounty level.  </p>
