It’ll actually be even harder, since they added another variable roll on it.
Assuming you want everything you want now (cold/lightning + IAS/CHC/Impale), but then a good (95+%) affix roll on top of that, and assuming the affix roll range follows a uniform distribution over it’s range (I think that’s the case for every D3 affix), it’ll be roughly 5x as hard to get a good one now.
For every one you get with the correct element + proper rolls, it’ll only have a 1/5 chance of rolling 95+% on the affix.
The lower value on the affix roll means that each point is worth a sizable amount of effective DPS, too. When it’s a 400% multiplier, an extra 1% on the affix isn’t worth that much in relative terms. When it’s a 100% multiplier, an extra 1% is worth a lot more in relative terms. E.g. a 100% HPS would be 14.3% more DPS than a 75% HPS. It’s going to be fairly important to get a good affix roll.
They need to add guaranteed CHC to HPS or something. It’s going to be so hard to get a good one.