need help with the avenger (or slow weapons in general)

Having previously only used fast swords such as the snarble barb and striker series im currently finding it quite difficult to make good use of my new avenger. fewer opportunities to shield during the two hit attack cycle is causing me to take far more damage against multiple mobs than i would have when using my previous swords.
My largest problem though is the small (but still significant) period of time after your second attack where you are unable to shield or move. Its during this space of time that im taking the majority of damage. What changes in playstyle do I need to minimise damage taken during this time?

If you use the first swipe of the heavy swords against melee enemies with the correct timing, most of them will miss due to the knockback, and you can use that.
But I don't like using heavy swords when there are quick ranged enemies around, like devilites. Even the delay after the first strike is too much for me against them.
Don't forget that you can shield cancel most of the animation after striking and charge attacking, it'll save your butt.

A few days ago I found a forum regarding heavy sword techniques. I think it may help you.
http://forums.spiralknights.com/en/node/13083
If you want a way to increase attack speed get the Vog Cub set and/or Swiftstrike buckler.
http://wiki.spiralknights.com/Swiftstrike_Buckler
http://wiki.spiralknights.com/Vog_Cub_Coat
http://wiki.spiralknights.com/Vog_Cub_Cap
first to remember:
You don't really need to release the second attack. take your time.
since you came from the fast sword lines, your mindset was to release all the strikes. You just have to consider this time that you deal more damage in one hit...
second:
The second hit is when you have confirmed that the enemy has finished attacking, or if you feel that it would take longer for the monster to launch an attack than one more strike with your sword (causing it to be knocked away)(which requires experience).
for example, never rush the strikes on the lumber series monsters. you don't negate their rate of attack anyway. same goes for gun puppies
third:
shielding is the way to go anyway...
When you arrive at the higher strata, damage is huge, enemies are (often) more than in lower ones. This means most of the time you WILL really be shielding a lot, striking less. Mechaknights can attack thrice, and you can stop them unless they die or knock them back. Proper shielding then attacking null this.
fourth:
Position yourself wisely.
especially (again) on lumbers and gun puppies. as much as possible go behind lumbers, alternating one strike, and shielding. once the lumber attacks, you are free to use the second attack (probably even an extra first strike).
fifth:
Use the knock-back.
The most important ability of the slow swords is knock-back. it WILL save your life more often than not. Don't be too reliant on it though when you are cornered by many foes. You attack slow remember?
sixth:
AOE/Cleave advantage
In my opinion, dealing damage to most number of opponents, though slowly, would take the same time as dealing with them one by one....
last(from me):
Charge attack!!!
For sealed sword series, this gives whopping damage, and a projectile. For the Troika series, huge damage as well, and great AOE coverage!
BUT time it well.
well.. many more actually.. I'm a fan of slow swords because of damage (in fact im using Skolver instead of Vog). I dont really feel using the compensation for attack speed since I can freely say that I am wise in pressing the right click button, making the most of every attack...