For the anthracnose are you using a fungicide? That is the basic recommendation - regular fungicide spraying (weekly or per label directions) from the first day of plant out. Daconil is the one that has been found to be the most effective. Since the weather factors that so contribute to the fungus growth are beyond our control the preventative measures are about all we can do.

Beyond that are the cultural controls: well draining soil, crop rotation, increased spacing of plants to improve air circulation, use of thick layers of mulch, remove all infected debris from the garden ASAP, spray other crops of the same family as well as the tomatoes, avoid overhead watering, good weeding practices, etc. etc.

The flea beetles have no direct role but as you mention they can, like any other pest, so weaken the plant and make it more susceptible.

Flea beetles usually pose no real risk to healthy, well-established plants but approved pesticide use can prevent a major infestation. If the pesticide use doesn't appeal then Surround (TM), a kaolin clay based spray on coating has proven to be effective in controlling flea beetles. Some studies I have read indicate that Spinosad is also somewhat effective although they aren't listed on its label.

Hope this helps.

Dave