Another possible use of remodel is just to bootstrap low potion cards into higher ones (university=>golem or golem=>possession). This is useful because low potion cards are easy to grab, but it's usually the high potion ones that are game changing. Also, university/apothecary are a lot less cool once you have golems (and want to maximize the chances of hitting "powerful" cards). Similarly, upgrading/remodeling familiar mid-game is useful.
Also, it can help if there is no +buy card, given that it cheats its way around it. So adding it to make a province+ duchy turn is even province +estate turn at the end of the game is valuable. (or as mentioned, province + cycle province turn to deny a province to your opponent).
The last use I can think of is similar to upgrade, but less effective: If you draw your whole deck, you can remodel a card, then use a cantrip to draw it and play it in the same turn. Again, nothing grand in most common scenarios. There are a few really impressive strategies though based on that concept. Most of them revolve around upgrade, however, because it already has the cantrip built in.
Overall, a situational card. Can be a decent opener if there is nothing else impressive at 4 or 5.