A very nice bayonet mod can be found at TWC here : http://www.twcenter.net/moddingnews.php
If not having bayonets has bugged you as much as it has me then you will really enjoy this mod. The grasp of the rifle stock by troops at the charge position is slightly imperfect but this is a niggling complaint. The sword bayonets of the period look good. The site has more details. Combat values change also.
This is a huge plus for me because tactically, as far as I'm concerned, these games can never be too historically correct.
It is very easy to install and backward compatible with old saves and replay films, too!