There is still zero reason to fit a gun on these ships. The total and absolute expectation is pure tank. Assuming it's going against a gang of subcaps or a gang of supers, the guns on these ships are pretty much pointless. Also it is the expectation that these ships fit multiple bubbles (2 at a minimum) and ontop of that, a probe launcher, or a cloak, or both. Assuming all, that leaves maybe 1 or 2 highslots available, which will have maybe a small laser because everybody put all their powergrid into their tank.

This does not change the fits or expected use of the heavy interdictor. People will not see its offensive capability mainly because people won't fit it to be offensive, just a brick so stuff can't leave a gate or the field.

Something has to be addressed with the weapons, the amount of warp bubbles the ships need, it's offensive capabilities against capitals and supers (they have none except to hold them and pray).

There cousin the light interdictor now has capabilities for fitting a tank, and having offense. The heavy does not (not that they do not have the option, but those who choose the options are ridiculed because they did not perform their role in absolute certainty)

siege should give you a weapon timer just like bastion gives you one.