This case is not about felonies. I should have made that clear earlier.
What Morin is about is the MA lifetime ban on someone convicted of a non-violent misdemeanor involving a firearms or ammunition for which a prison term may be imposed.
Morin's situation is he was convicted (pled out, I think) of a gun misdemeanor in DC that has a theoretical prison possibility. Comm2A is arguing it is a violation of his rights to impose a lifetime MA ban under these circumstances.
Unfortunately, this has no bearing on the MA misdafelony situation but is widely applicable to persons with non-MA minor gun cases. The "prison term may be imposed" is misleading as to the severity of the underlying crime as there are offenses where this possibility is on the books for an offense but only very rarely if ever imposed.
An excellent example is discharge of a firearm within 500ft of an occupied dwelling without consent of the persons occupying said dwellings. The penalty is up to a $100 fine or up too 3 months in stir. Since it involves firearms, and has possible jail/prison time, it is a MA lifetime DQ. This is particularly disturbing given the recent MA SJC (or SMC) decision that this is a per-se offense not requiring any intent for conviction as the penalty is so minor. The court made no mention of, and apparently did not consider, lifetime MA deprivation of a civil right as part of the penalty - it was apparently ignored because it did not fit the agenda of the decision they wanted to issue.
As to the other issues - one sure route to failure in a gun rights case is to make it two broad, as one is just giving the court many hooks on which to hang an adverse decision. Some of the issues of which you speak are being litigated.
The Boston range test faces an additional litigation obstacle - stare decisis. This was already unfavorably decided in MacNutt vs. Police Commissioner of Boston, although that case did succeed in eliminating the charge for that test.