ive got a 24 inch bitch witch i consider a good allround bitch in all terrain on all quarry but have seen certain dogs better on certain quarry on terrain suited to them i.e a 21 inch wippet/irish terrier in paddocks or on close slips on rabbit shes killing 20 plus out of 25 runs but she only kills rabbit and so on the main important thing is to remember an allrounder is exactly that not specialist at one paticular job but good at everything i think purely due to physicall ability 24 ins would be of minimum size to do the job properly just my opinion