I think it is a good way to choose RF first. I would do this:
There is a filter thumb rule, that if you are using a feedback topology the open loop gain of your circuit should be at least 20dB bigger at the cut-off frequency (Fc) than the closed loop gain at Fc.
The loop gain of the OTA is depending on the Gm*Rout, where Rout will be close to RF. So to find RF you have to know the Gm of the OTA, and the desired gain first.
At higher output voltage swings a higher current will flow through RF and CF, so you have to be sure that the OTA's output stage has enough output current capability. If it is not enough, increase RF's value or the current of the output stage and be sure that it doesn't decrease the gain at Fc.
Be cautious with too big values of RF because it can make your circuit noisy, and sensitivity of filter parameters will be higher for parasitics.
To find CF use the formula by biff44.