I know its a common comment about iPhones, but wait till next year, for the next design refresh. If your phone is mostly serving you well, may as well hold out for the biggest possible upgrade.
I can see that argument, but on the other hand, the first iteration of an iPhone design refresh tends to be the one with the most problems (antennagate, bendgate, etc.) The 11 Pro seems to be peak maturity for the "iPhone X cycle" and has been reviewed very favorably in all respects, it might be worth just getting one rather than betting on an unknown quantity.