As with many here, I'm disappointed (at least intellectually) in the choice here. I would think that they could have made two options available, either enabling full functionality of the iOS versions through an IAP or through Office 365 subscription. They could have made the IAP something like $20 for each app, and I'm sure they would still have had people choose that option over the subscription alternative.
As for hate aimed at the subscription model for software, there are a lot of reasons to dislike this model, from the consumer's perspective. The flip side is that there are a lot of reasons to like the model from the vendor's perspective.
First off, there is cost. If you compare cost of the subscription to the cost of the software over the life cycle of a given version, usually the subscription is a little less. However, if you follow the common consumer upgrade model and skip one or two versions between upgrades, then suddenly the subscription model can cost close to two or three times as much.
Second, there is life of the product. Under the subscription model, if you stop paying for the product, it stops working. Period. So, if your use slips down to only needing to access a file once every couple of months, you can't decide that the version you've got is good enough and figure you're done paying for it. If you do that, you lose your ability to access those files, even on those rare occasions that you need to,
Also, frequently, when an update is released, it is mandatory. Like things the way they are? Don't feel the need for the changes in the new version? Don't like the changes that were implemented in the UI? Tough.
Finally, and perhaps most importantly, the subscription model does a lot to eliminate the motivation from the developer to continue to innovate. If they keep getting paid for the work they did last year, why do they need to do more work this year?
Yes, there is still the pressure of competition, but the very nature of this discussion (Office is THE standard for office apps) makes it clear that competition doesn't necessarily apply as much pressure as trying to convince current customers to upgrade does.
So, yes, I am not someone who is in the subscription fan club. I think it is a bad idea and it takes more power away from the consumer and puts more in the hands of the corporations. Bad, bad, bad.