Mining Blaster is the low-tier Open Market armor cracker for Energy ships that was probably designed for enemy Ventures or civilians drawn into combat. It should have its DP lowered below 10 to be more like other low-tier Open Market weapons. As for when to use it, Apogee starter starts with it (and can support it), and there is nothing much better against heavy armor until Heavy Blaster or Plasma Cannon (or HIL/Tachyon if Apogee has Squalls) comes along. Later in the game, after I have all the weapons I want, I never use it - too inefficient and not enough range. It used to be useful for Hyperion when it had unlimited teleport before its recent redesign, but now it is no good for Hyperion anymore.
Heavy Burst Laser ignores countermeasures, so if I want burst PD but do not have IPDAI (or want more range than burst PD), I may want heavy burst laser. Also, it is more efficient than phase lance (and has +200 if ePD is involved), so if I stack a few, I have a phase lance alternative (instead of one Phase Lance and two Tactical/Gravitons) that is more efficient (and more range if the ship has ePD). Better anti-armor than Tactical Laser or Graviton Beam. Works fine against human fleets, but admittedly underpowered against Ordos.
I use the following in medium energy mounts.
* Heavy Blaster - for big ships that can support it, or SO ships.
* Heavy Burst Laser - burst PD with more range; light anti-armor if the ship can focus several.
* IR PL - Two is superior to one Pulse Laser when ship has ePD+IPDAI, and many ships have smaller mounts to spare.
* Pulse Laser - shield cracker or flyswatter on ships without ePD. Mediocre option all-around.
* Phase Lance - strike weapon for Harbinger. Okay as flyswatter on some other ships.
* Mining Blaster - Apogee starts with it, and it will do until I find a heavy blaster or plasma cannon. (Upgrading missiles has higher priority.)
* Ion Beam - rarely use, it takes too long for the beam to EMP an enemy.
* Ion Pulser - finisher or non-missile PD.
* Graviton Beam - rarely use, and most of the time I do use it, I also use High Scatter Amplifier to give it hard flux.
The new kinetic blaster will then likely fill the hole if none of the other weapons work as it will certainly be efficient vs shields and it is described as being like the heavy blaster which is good except for it’s flux.
If kinetic blaster is much rarer than standard human weapons because player cannot buy, order, or (with blueprint) mass-produce them (and must kill and grind LG Executors for them), I would not count kinetic blasters as a feasible option because they would be too rare, especially if Lion's Guard is less common than Ordos.