With all the other buffs coming to medium energies I would not say no to a phase lance buff, but I will also say that in its current form I use them frequently alongside kinetics and for burst damage builds, including on non-high tech ships that you'd think the poorer efficiency would be important on. The current weapon works.
For phase lances, doing full damage to shields and being in a burst makes their being soft flux matter less - it still matters, but the damage is delivered quickly enough that high flux targets can't dissipate it during the burst. And because its a beam, even overloading doesn't actually save them from the damage the way it does with high per shot damage projectiles. I do wish the AI would fire them less frequently into low flux targets when backed by kinetics, but burst weapons are trickier than ammo weapons in terms of shot conservation.
In terms of dealing with shields, 214 soft flux/sec at 1.2 in 1250 spikes is imo much better than 87.5 hard flux at 2.0 (I have no idea what the initial spike size will be, as the revealed stats are confirmed to be being tweaked downwards in terms of burst). I'm very happy to hear that the mining blaster is going to have custom fire logic to preserve itself and not waste into shields! Thats going to make it way better at its job of armor and hull killing.
In terms of anti-hull, I think they are going to be nearly equal at DPS once the mining blaster's burst is down, as the MB has lower DPS but better penetration (700 vs 500), but with better efficiency. Otoh, even high flux shields can 'catch' mining blaster shots safely, while they really can't catch phase lances... I'm really unsure here. I think for medium-armor targets I might prefer the phase lance depending on the burst and accuracy of the mining blaster! Also being able to get 800 range (with advanced optics) vs 500 is a decent difference.
Uhhh I kind of rambled there, but I think a firing logic tweak (and the aiming bug being fixed which we know it is!) would be just as important as a small stat change to making the phase lance keep up well.