IMO the problem is somewhat mitigated with the modified table, but it still exists. While previously the criticals (until reaching a 'V' crit, which is killing anyway) were just the same for an unscaled and a scaled version of an elemental attack spell, each scaling now effectively increases the critical severity the caster can expect for his attack by one. Additionally the difference in concussion hits between the different attack sizes is now more pronounced.
This is certainly nice, but OTOH it does not equal more than a +5 bonus. Would I have my spell caster invest 5 PP instead of 3 PP for an Elemental Bolt, putting almost double PP into the spell, for such a small bonus? Or scale up the spell even higher requiring more than one round to cast? Not often. Better shoot two tiny bolts instead of one medium or larger one (2 chances for a good critical roll). Firing a small bolt instead of the tiny bolt might more often make sense.
Whether scaling is useful certainly also depends on my bonus with the Elemental Bolt/Ball spell and the opponent's DB. If my spell caster has a low OB and/or the target a high DB, then scaling might make sense to increase the chances to get a critical at all or for getting a good one. But if instead my spell caster has e.g. 120 OB with his Elemental Bolt and the opponent has a low DB, so that I might have something like 90 + dice roll for my attack, then chances are quite high (almost 50%) that the spell caster reaches a result of 146 or more, which would be an instant kill. Increasing these chances for a killing spell makes little sense. Instead just cast again next round with the same high chance to kill. This is IMO a fundamental flaw of the H&S system, that once just reach 146-150 or max out the chart, then you have a guaranteed instant kill. That's even true if you use a dart or dagger against a super-large creature. And this flaw does not get removed with this change.
I think it helps taking a look at RM's Spell Law attack tables or the MERP spell attack tables. If you compare a small spell attack, like a Shock Bolt, to a larger attack (i.e. the equivalent of a scaled version) like a Fire Bolt, then it in most cases makes sense to use the larger attack version because only that is able to achieve the higher criticals. The maximum for a Shock Bolt for most ATs is IIRC a B-Critical, while for a Fire Bolt it is a D- or E-critical. And that means significantly more stuns, bleeding plus double or higher chance to get a killing blow.
With H&S the incentive for using a scaled version of an elemental attack spell is significantly lower (at least for a power gamer) and it often does not outweigh the costs (in terms of PPs, time and increased spell failure severity).
Just my 2 cents