I'm sure if Caesar had gone to Illyricum he would have made himself there too ;-)
Actually, the initial plans were made because there was fear of an invasion by the Dacians; these eventually turned back and never reached the border but one may imagine Caesar playing upon that "threat" or fighting the tribes who were so much trouble for Piso in Macedon in the following years (Denselatae, ecc).

As for the De Bello Gallico - it is so interesting, and it reads like an adventure book, doesn't it, cowboys and indians in the grand scale? Very cinematographic IMO, you can see the battles as Caesar describes them. And the suspicion that he was not totally objective (there are many papers written on this) does not detract from the readability.