Neutralizing great armor save

I've had a couple recent losses that have greatly annoyed me. A lot of the issue I can blame on the dice (Tyrant & Bruiser that rolled 4 hits in two turns in game 1, then SM and Bruiser doing similar in game 2).
I've added Obsidian Blade as a must have against WoC and Empire.
Bonecrusher is good for small units.
Death has a lot of 'ignores armor save' options.
Twin Ironblasters help some. Playing ranged/avoidance has only been so so - lots of knights/juggs/etc catch up sooner or later.

So... What do other people do to deal with an enemy with 1+ and 2+ saves on the majority of their army?  WS4+ seems very common as well.

Ironguts with a Maw Slaughtermaster (Glittering Scales, Fencers Blades, WS) and BSB in the unit. Add a Beast Butcher and cross your fingers to get Savage Beast and Wyssan . It's another version of the Gutstar but it might work.

Gorgers might work vs High Armoured units as long as they aren't monstrous, but they might die as well.

Other than that, it's pretty much what you said. You can also try to avoid the highly armoured units until you've cleaned most of their support. Lone Sabretusks and units of regular Gnoblars should give you some valuable chaff to take care of those annoying units until you are ready to engage them.

Other then that, the best advice I can give you is to focus fire with your magic/shooting. Spreading the tough love won't help you at all, the opponent will just cross the board with units that have been slightly injured but nothing dead. When you roll well, it might lead to overkill, but if not, you will have just enough to do the job.

Ogres are very well suited to dealing with troops that have high saves. Ironguts are Core and slap on -3 armor, Mournfangs combine -2 armor with a busload of attacks, and Maneaters can take it to another level if necessary by taking Great Weapons and imposing a daunting -4 armor, as can characters (sometimes while striking at Initiative order!). Additionally, Ironblasters rip right through any sort of armor, and several Lores (Maw, Beasts, Death) will allow you to deal with it by ignoring the save altogether or pumping your Strength up even higher. You should not have a problem countering armor, and you should definitely not be resorting to overpriced items like the Obsidian Blade, especially in an all-comers list.

The key here is to employ the strategy described by SeBM - focus fire. They're going to make some saves, and that's OK. Keep hitting them and they'll fail enough for you to win.

My friend runs a Tyrant with giantbreaker and a giant's blade when he faces monsters. Other than that the Ol' Ironguts with Wyssan's or a stonehorn and and Wyssan's. Ironblasters ignore all armour possible (like someone has -2 armour)