No, SMs shouldn't get lances at all. The bombardment cannon variant of the SC is very strong. I think too strong. The problem lies in the fact that it swaps a lot of essentially defensive weaponry for a good deal of purely offensive weaponry. As noted, the SC packs a whole hell of a lot into its little frame. Too much by rights, particularly from a model point of view. Looking at the prow of the ship, for example, the SC gets nearly as much firepower in its BC as the Dauntless has. On top of this it also gets 2 THs, in the same hard point. That prow must be huge to be able to fit all that in. Particularly as 2 THs are worth at least 3 normal AC in terms of bay size (a Styx that is converted to carry THs only has launch capacity instead of 6, and that's the best it ratio there is). So the SC model is supposed to be able to justify 3AC and 3BC in the prow. It doesn't.
So a few of us advocated dropping the prow launch bay to a strength 1 TH to make it more reasonable. Of course, SMs don't really need nerfing, and they do have survivability issues as it stands, so the idea was to compensate them for this loss by adding the extra shield for free. So basically, you get a 2 shield 1 TH SC for 145 pts. Using this prow launch bay as base we were able to "fix" the variants. You can swap the TH for either 3 torpedoes or 3BC@30cmF. So instead of getting roughly +3 lances on top of the ~2 it already had (2-4 extra dice hitting on 4+), it gets only +1.5 lances (1-2 extra dice) equivalent in firepower.
This works out reasonably well. Since 1 TH = 1.5 normal AC and 1 normal AC = 3WBe, therefore 1 TH = 4.5WBe. As 1 lance =3WBe & the 3BC ~1.5 lances then it also roughly equals 4.5WBe. One torpedo = 1.5WBe so the 3 torpedo option is also worth 4.5WBe. So all of these options are weighted equally. While Thunderhawks are more defensive in nature than either the Bombardment Cannon or torpedoes, these weapons are locked to the front arc, meaning they cannot focus on the same target as the broadside weaponry. So if you've only got one target you've basically got the choice of closing and firing 6 BC or presenting a more defensive aspect and firing 3 BC and 4 WB. The standard TH would, of course, go for the latter arrangement and it would have a TH to add to the fleet.
However, this change in the base number of THs on the SC effects the fleets carrying capacity. With an already reduced TH load and then a few ships foregoing them altogether in favour of BCs or torps you run the risk of being overwhelmed by enemy bombers. So a carrier SC variant was proposed, replacing the broadside WBs with a single TH bay each side (for a total of 3; prow, port and starboard) at a premium of +15 pts. So if you had 1 normal SC and 1 carrier SC you'd get 4 THs in total, the same as you do now from 2 normal SCs. Lots of variety and ability to customise your fleet, without having 8 Bombarment Cannon Strike Cruiser monstrosities.
