You may be at the stage I got to with my R1800, it just became unreliable. Whether I use up the printhead lift or nozzle life or what, I do not know. But it just stopped making decent prints reliably.
I think I would look at a new printer. If you're happy with the features of the R1800, go for an R2000. I think you will find that Epson has vastly improved the automatic head and nozzle maintenance. I replaced by R1800 with an R1900 4 years ago and it is very much trouble free.