I'd like to chime in and also comment on the Beamers. They are Heavy weapons and Wraiths are not relentless since they are not part of a Canoptek Harvest and, thus, will probably never use them.
I also agree with dropping
MSS and Phylactery, it just makes sense, they're not very good wargear options.
I would suggest, for the same cost, if you want:
2+ save/ 4++/Warscythe
and put him with the wraiths. Try to keep him at the front so he tanks any volume of fire with AP>=3 and the wraiths "look out sir" for Ap2 shots. It's great to keep your wraiths alive longer, since they miss the
RP from the Decurion/Canoptek Harvest rules.
Otherwise, the Voidreaper +phase shifter is also a legit option for less points. Makes your lord way more dangerous.
Besides that, 6 destroyers in a single unit are 1) easier to deal with thanks to cover saves/
LoS blocking and focusing fire on a single unit. 2) it's overkill
You're wanting to kill
MSU marines and scatbikes mostly. 6 Destroyers are probably going to waste a lot of shots shooting stuff that's already dead.
For the tomb blades, I'd also argue the same, however they're cheaper and benefit from Jink saves and your
FA slots are crowded so, it's kinda better. However, if I was you, I'd drop down the squad sizes for the Tomb Blades and put 2 units. (For that I'd completely drop the Destroyers)
Or drop some points from elsewhere, like the warriors or tomb blades and include a full Destroyer Cult. You already have 6 Destroyers and 1 Destroyer lord in the list. If you include 3 more destroyers, you free your fast attack slots and you also earn an AMAZINGLY good rule ("extermination protocols"

for your destroyers.
Other than that, it's a solid list.