Good sets - used that combo for a long time.. (only with one pet tho)
Not sure about your skill choice though.. I would..:
Drop healing ward - With twilight matriarch, you don't need it. Either take harness or use the slot for inner light - or another offensive ability (see below)
I'd also go for more ranged, single-target ability - ie.
switch from frost to flame (shields should be big enough to not need the frost block benefits)
use the standard curse/frag/CS rather than reach/blockade/mines
This lets you fight effectively at max-range, making it less likely you will get ganged up on (shields don't do well when outnumbered) - and more likely you can escape when outnumbered.
but that's just how I like to roll. (personally, I'd drop the volatile familiar for open world too - but that isn't what your build is about).
Oh, and it's VERY risky using overload offensively without a shield on your overload bar..
The problem with overload is its clunkyness with enabling/disabling it. I counts as a full ability unlike a normal weapon-swap - so you can't ani-cancel with it like a normal weapon-swap - and you have to wait for your current ability to fire first before using it.
Lets say, for example, you're on your overload bar in the middle of casting something - and you get ganked by a nb, taking down your shield and a bit of health. You now need to re-shield very quickly... but first, you need to :
1. Wait for your current attack/ability to finish (lets say half a second)
2. switch overload off - 1 second
3. cast your shield - takes almost a second for it to take effect.
That's 2.5 seconds from the initial hit to getting a shield off.. You're already dead by then. So basically, if your overload bar only has out of combat utility stuff on it (like rapids, defensive run etc) - don't use it to fight with. If you want to fight with overload - it needs to be built as a combat bar - with shields, other damage abilities (curse ideally) and possibly some cc. Which is difficult with 2 pets.
In terms of long/short range - and single-target/aoe:
Mines is a useful defensive mechanic - rated by many players - but I've had limited success with it, and always find better options on my bar. Yes - you cannot avoid melee fights... but when its many v many, and one guy rushes in to melee while the other are doing ranged damge - its that melee guy who puts himself in range of everyone else and so dies quick..
If as a sorc, you get hit by 3+ melee opponents gap-closing at the same time - you're either dead - or full on the defensive (shield, shield, dodge) before being dead very quick.. You won't be able to attack them much.
If its one guy - you have a reasonable fighting chance - which is probably better with single-target focussed abilities.
The combo of abilities you chose - with it's CC may still work well in these situations (I've honestly never tried) - but they will be gimping you with ranged encounters due to your limited bar-space..
But then the downside of attacking ranged targets for you is with the volatile familiar. It will keep dying. If you're adamant on using it, your setup could work but would have to rely on keeping your pets on passive, and trying to lure individuals to come to you where you can put them on aggressive.
But you may find that with mines down, they can either just tank through them or will stay away. If the former, they are VERY expensive to keep replacing. Also, opponents usually just move out of gtaoe's (which is why I don't like blockade). The theory could be that you can just stand in it while they have no choice but to come to you - but if your setup is relying on 'setting up house' ie. mines/blockade) and fighing on that spot - the reality may well be that in most cases, that one guy attacking you is followed by others so you don't want to be in that spot anymore. you will need to be mobile as the ebb and flow of the battle moves. In many cases, 'setting up house' can often end up being a waste of resources.
But on the other hand is very useful at chokepoints like keep-doors etc.
Good luck out there!