Once again I consider the gordian knot that is the Rifts ruleset. Particularly how to make BOTH SDC and MDC combat occur, not just one or the other. Of course the author (Kevin Sembieda) just forces players out of their armour (cause you can't wear it all the time) then has a bear turn up, coincidentally, just at that time. There, done and dusted in his opinion. Either you probably think what I think about that, or you think that works just dandy and I wont shower you with my dismissals.
Anyway, for the former camp, this is the method I'm thinking of to blend MDC and SDC threats. For one, alot of SDC monsters, together with their SDC attacks also have a psychic slam or psychic blast attack. This attack does 1 Mega Damage (or 2 Mega Damage on a crit) on a hit. During their melee attacks, a natural 18-20 on the dice rolls means instead of doing a normal attack, they do a psychic slam melee attack. Once they have done it, they can't do another such slam or psychic blast for an hour. Psychic blasts take awhile to charge up, generally done on the monsters last attack of the melee and similarly, once used the monster cannot do another psychic slam or blast for an hour.
Second is that the chest/torso plate of body armour can be removed and replaced with a homespun, salvaged armour (made of shards from old bits of armour and/or old pre rifts building fragments) that has 200 SDC and an armour rating from 12 to 15 (generally 15).
The thing is psychic slams and blasts are slow enough that the wearer can see them coming and opt for the armour to take the blow, making it automatically hit the armour even if the attack is above the AR or even if it's a critical hit! So it soaks the hit. But if it's hit even by just 1 point of Mega Damage, all of it is destroyed. If hit by a crit and it's already taken damage, the PC takes the remainding damage.
Eg, if it had been reduced to 190 SDC and a psychic slam hits it with a crit for 2 Mega Damage (200 Standard Damage!), the armour is gone and the PC takes the remaining 10 damage (200-190 = 10 Standard damage taken)
So, if you get the set up, this basically works if you have a low cash campaign - you don't want to wear your normal armour all the time, because even one point of damage costs alot to repair (assuming you can even find a repair place). So instead you want to wear this armour and attack with SDC attacks, soaking the psychic slam/blasts with the homespun armour (which simply costs time and effort to make, rather than money).