1. Direct-fire engagements by manned vehicles are the last resort.
2. RPVs are preferred for reconnaisance and direct-fire engagement tasks. The smaller, the better.
3. Given that hiding a full-up MBT is kind of hard, and that most engagements will be in urban areas (Ralph Peters: "In the future, 'urban combat' will be a redundancy"), the main threat that the FCS manned vehicles will face is the RPG and mines.
4. The preferred defensive schema of the manned FCS flows from this, in order: avoid detection by enemy heavy forces (first line of defense), deflect/kill RPG rounds via active defenses, detect/avoid/neutralize mines, have enough armor to prevent significant penetration by an RPG round or REASONABLE mine, be able to take SOME (not a lot) of penetration by an RPG without killing the crew or the vehicle.
4. The preferred defensive schema of the manned FCS flows from this, in order: avoid detection by enemy heavy forces (first line of defense), deflect/kill RPG rounds via active defenses, detect/avoid/neutralize mines, have enough armor to prevent significant penetration by an RPG round or REASONABLE mine, be able to take SOME (not a lot) of penetration by an RPG without killing the crew or the vehicle.
Two other vehicle killers you'd better factor in: advances in *fire and forget* and SACLOS AT guided missiles like AT14/9M133 Kornet, AT15 Khrizantema, Javelin, Ground-launched Hellfire [MBT kills from 10KM!] and LOSAT. Granred, the payback is much more cost-effective if they can be used for a tank kill, but if they're used to wipe out a 9-man Stryker squad and its crew, that'll do...and imagine such an event in the light of today's one-or-two a day casualty lists from Iraq.
The other consideration is mines, not the conventional ones you very reasonably are concerned with, but a much smaller, command detonated shaped charge warhead, implanted in the ground and fired by remote control into the vehicle's thinnest belly armour, either by wire, radio or laser designated command. Think of it as a Claymore mine for vehicles...and an improvised version would require nothing more than a PG-7 HEAT grenade warhead, a golfball-sized lump of C4 or Semtex, a doughnut roll of commo wire and a claymore firing clacker....
And if the much-vaunted *metalstorm* roman candle charge technology comes to pass, consider the possibility of a DIPCM mortar version, activated by sensor and raining a preset number of semismart projectiles down on and armored vehicles, light or heavy, that come within the tactical area of responsibility if its basic sensors, or additional data fed to it by anything from a recon team to a JSTARS data link. That too, can make life hard for crews, whether wheeled or tracked. [Though tracked crews can do more to avoid the road juctions that are likely preregistered targets for artillery FOs, minefields, and future developments that capitalize of the control of such chokepoints.
And we're probably overlooking one or two other developments that'll help ruin the day for some of those future troopies. But those listed are bad enough news.
-archy-/-