When I tried them at the rink, my balance seemed to be gone. I was tottering along almost like my first day back on skates. When I tried to do a snowplow stop I couldn't do it to the tune of a couple of falls. It's like I forgot everything I'd learned in the last couple of months. Then, pain in my feet soon got too bad to continue. All in all, a very frustrating outing.
Forward/back Balance or side-to-side balance? E.g., do you feel like you need to work to prevent yourself from falling to the inside or to the outside? If so, which one, on which foot/feet? There is a very good chance that this can be fixed by items 2 or 3 below.
AFAIK, arch pain is usually caused by one of several issues:
1. At some point along the skate, the skate is too narrow. It is pinching part of your foot. That can hurt. In addition, pinching the foot from the sides forces the arch upwards, sometimes to the point of discomfort.
2. There is a mismatch between the shape at the bottom of the skate and the bottom of your foot. You want approximately equal pressure on all parts of the bottom of your feet. If some part isn't getting as much support as some other part, or feels like it is being pushed into an uncomfortable shape, remove the insole, trace it on a piece of foam or a bigger and thicker insole, cut that out, and cut down the insole in a 3D sense to get equal pressure everywhere, and put the insole back in. Or add tape underneath one part. Or trace it on a piece of foam, and cut it to shape, in a 3D sense. E.g., if you feel like you have less pressure under the arch than on the opposite side, you could add tape under the part of the insole that is underneath the arch. That said, people whose feet collapse asymmetrically under weight (so that, for example, your foot tilts to one side as you put weight on it) sometimes need slightly unequal pressure to counter that problem.
3. There is a side-to-side balance issue. You keep having to use your muscles to stay in balance. Balance is affected by the side-to-side positioning of the blade (sometimes called "offset"), and by the 3D mismatch problem I just mentioned. Most skate techs for adjust this by changing the offset, but I eventually decided I am better off adjusting it by changing the shape of the insole. In particular, if you adjust offset too much, it creates other problems with things like spins, and some boots can be damaged by off-center weight loading.
4. The heel is too high. You simply aren't flexible enough for that heel.
By the way, instead of changing the shape of the insole by hand, some people prefer to use a heat-mold-able orthotic. It costs more, but it is a bit faster, and you don't have to figure out what to do, especially if you pay a podiatrist, PT, or other qualified expert to do it. Me, I'd rather spend a few pennies on tape, or buy a cheap piece of foam (I bought a $7 camping pad, which is big enough to make many insoles - it eventually squishes down and needs to be replaced) and cut it down until it feels perfect, than to pay an medical practitioner to MAYBE do it right.
There is also another possibility with balance: maybe you just need to get used to the new skates and blades. However, that doesn't explain the pain.