ffmpeg is slow on CPU, it would take around 10-20minutes to render a 2 minutes video on CPU where as if you use GPU rendering it would take only 1-2 minutes. if you go for VPS it would even slower as virtual CPU are shared among several customers. if your work load is too much then better to get a GPU based server, you can checkout cheap GPU host on vast.ai or vultr, if you are technically proficient then you can try runpod as well.need a webhosting with ffmpeg