My thoughts. First of all take a look at RAAF training. The course is around 210 hours all on a single engine type. The pilots graduate with an instrument rating. It would be inconceivable for the RAAF to send a newly graduate pilot to a squadron without an instrument rating.
There is a logic in undertaking an instrument rating as soon as possible either during or after CPL. Forget VFR hours making you a better instrument pilot. Those hours mean nothing.
Despite fine weather most times up north or other parts of Australia, there will be times where a VFR pilot can be caught out - not necessarily through his own fault. Commercial pressures are real and the temptation as a new VFR charter pilot to cut corners to please your employer will be strong. You might find yourself in cloud or bad visibility or a black really black night where you need instrument flying skills to survive.
The 10 hours of dual instrument flying instruction required for a CPL does not prepare you adequately for the first time you are seriously on instruments (inadvertently or otherwise) without an instructor holding your hand.
Whether or not you can afford a multi-engine instrument rating is for you to consider. But get an instrument rating before you start job hunting and doing it on a single is one way that is affordable. There are flying schools who recommend you combine the initial twin endorsement with a multi-engine instrument rating. That gets expensive as it is all multi-engine dual.
There is nothing to stop you however, to starting the instrument rating course on a single and then change to a twin for the last few hours. Be prepared for grumbles from the flying school if you go down that path. Once you are reasonably competent on cross-country instrument flying in the single as part of the course, switching to a twin to finish off makes good sense and is cost efficient. If the flying school claims it will only do full instrument ratings either on a single or a twin but not a combination then go elsewhere.
Another point worth considering and that is the vital importance of being equally competent at instrument flying on limited panel as on full panel. By limited panel I mean without the main artificial horizon in front of you. That leaves an electrically powered Turn Coordinator and an old fashioned magnetic compass. Vacuum pumps are known to fail. Limited panel is best practiced initially on a synthetic trainer and includes take off and initial climb, unusual attitude recoveries, holding patterns and instrument approaches on limited panel. There are older pilots who were taught spinning on limited panel and recovery. That took considerable instrument flying skill especially if vertigo hit you during the spin.
Even after you have gained your instrument rating ensure you try and give yourself an hour a month in a synthetic trainer on limited panel. It can be a life saver and money well spent. EFIS instrument panels are very reliable but you can be sure that one black night in your career you will experience an event where the normal artificial horizon gives mis-leading information or fails completely. Read the ATSB report about the Piper Aztec that departed Moorabbin with a defective AH and was lucky not to have lost control in cloud
Finally:
Once you're in the game with a couple of hundred hours under you belt, when you see that further investment in yourself and your chosen career may be worth something then go and do your mecir.
There you go- another Ppruner suggests a different slant on things. He might be right but it becomes your call.
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