You might have to do a lot of head cleaning passes to make them work again and with Epsons it doesn't always sort it out. I have mediocre success using head cleaning fluid but it starts to get messy then. I don't know where you are this fluid is in Brit prices.
Epsons can be a PITA because the print heads are part of the printer and quite apart from the fact that they are a nightmare to replace (well I think they are) they are, usually more expensive than a new printer although that does depend on how much your printer cost.
I sometimes don't use mine for a month or more. sometimes i have to clean it or not. Sometimes the ink will dry out and cause the marks you have ( lines,Muddy pictures, Odd colors for print.) I make sure i have full or mostly full cartridges that helps with it. I find that if the cartridge is almost empty its hard to get ink flowing again, even if i change the cartridge. Myself, i like Epson over other printers. Mine is around 3-4 years old and the one before was 7-8 years old. I couldn't get Hps or Lexmarks to work much over a year.
just my 2 cents, WD 65