I haven't done the calculation, but I suspect you need a bigger starter than that. I've heard Jamil say at least twice, "If you pitch enough healthy yeast, just about any strain can ferment up to around 15%."
And since you're looking for a super-malty beer, why not consider Wyeast 1968 or WLP002? I find these yeasts boost the malty perception in whatever beer I use them in. Without any late hops, you'll really want a lot of malt complexity in this beer and I think this strain can get it for you. The 1084 has some maltiness too, but I'd put it between the cleanness of 1056 and the maltiness of 1968.
And finally, even though you want something sweeter, I think you should bump up the IBUs to around 65-80. The bitterness will fade with time and you'll be left with a much sweeter beer even after only a year.