Idiotic idea, pools will dump DGB to the hell because only small amount of MYR miners will claim their FREE DGB coins. Check MON price charts, pools are dumping it regardless of a price. You will kill this coin offering merged-mining, all your efforts will be buried.
If it goes multi-algo dev must calculate initial difficulty for each algo and do something with readjustment to avoid instamine by SHA ASICs, FPGA farms, etc...
What type of algos will you have in place? The same as Myriad coin or different?
Otherwise our only option is to do back to back hard forks which is no where near ideal or feasible.