Canon T2i is still a good camera, but your needs and your level of demand may have changed in recent years. Speaking specifically about the current substitutes:
T5i will give very similar image quality, with more organic grain, with film like grain. The focus points are all cross-type (only the center in the T2i). Live view is faster and does not hunt for focus and enables continuous focus during video. The LCD is touch sensitive (works great) and articulate.
70D will give you all the advantages of T5i, and slightly higher resolution, and noise a little smaller. There are 19 focus points, all cross-type (T5i has only 9). Live view with Dual Pixel AF is much faster than any previous DSLR, and can focus without hunting. Making videos with Dual Pixel AF will be a joy, but STM lenses are needed to focus and quiet without "giving jolt." Battery life will be higher, and ergonomics facilitates use heavy lenses, with less fatigue. 70D allows AFMA to calibrate your luminous lenses, and more accurate focus when shooting using the optical viewfinder.
If you already have good quality glass, a better camera will be a worthwhile investment.