The GTX 750 Ti is within the vicinity of an RX 550, an HD 6950, and an R7 360.
The GPUs you mentioned (HD 7850, GTX 950, and GTX 760) are all better in graphics performance than the GTX 750 Ti in that order (i.e., the HD 7850 about ~20% better, the GTX 950 about ~50% better, and the GTX 760 about ~65% better).