I'm not necessarily advocating an new laser.... I'm just trying to make suggestions that may compensate for the potential "shortcomings". Even if it may be just a wattage upgrade to get greater depth.... but then again the extra depths is only beneficial if you decide to wood fill and then sand away any staining... you might be able to minimise it by careful filling. You may get away with masking and hopefully sand away the mask material after you've woodfilled and manage to sand away the excess with the mask before bottoming out... I just hate sanding away "paper" tape/templates etc...
If your first cut is too short... Take the second cut from the longer end... LBD