I've used Rodinal with the Efke/Adox 25, 50 and 100 films, and never found grain to be an issue. I tend to use Rodinal 1+100 at 20C.
You may want to experiment a little with the dilution & agitation of Rodinal first. The higher dilutions tend to show less grain, and with reduced agitation, lower the contrast.
If you do want to change, take a look over on this site (Fotohuis Rovo) at your different options.