You're getting confused with the FAA system.
Over there it's feasible to do the CPL exam (singular) and get your CPL at 250hrs. Then you can build hours, instruct etc.. (no multi-pilot required for FAA ATPL) and do the ATP exam (singular) and the ATP checkride. FAA ATP issued having never flown anything more than a C150. Good huh?
Over here in JAA-land, the CPL is 9 exams, the IR is 7 (but IR HPL credits for CPL), so to do it that way means taking 15 exams. The ATPL exams are almost the same, but there's only 14 of them as you're not taking almost identical exams twice (as you would for CPL and IR). The effort required for ATPL over CPL and IR is only moderate; things like global climatology, transonic dynamics, intercontinental nav which aren't required for CPL and IR.
To sum up, if you want to be an airline pilot in JAA-land get your head down and do the ATPL exams, then do your CPL and IR within 3 years of passing the last exam. Your ATPL theory credit is valid for 7 years (if memory serves) from your last IR renewal. Keep your IR current and the theory credit doesn't lapse. Then if you're really, really lucky you might get an underpaid FO job in a few years.