I can't see this being similar to the final form of FP+, it just doesn't seem to make sense, even from Disney's perspective.
I can't wrap my head around why they could possibly want people standing in lines more. That's exactly what this current version of the program is doing. The planners are waiting in line more, and the casual guests who do minimal research are too. For the simplest example, for our family at Epcot we FP Soarin' and TT. Now that we have to choose one, we will be stuck waiting in line for TT, not to mention waiting for Soarin' if we want to ride again (and we will). This same principal applies to all the parks, but it's especially obvious at the parks with tiers. At DHS, we now will be waiting in line for either RRC or ToT. At MK although there is no tiering yet, we'll still be waiting in line more than in the past because we used far more than 3 FP a day there. So basically, with the old system there was the possiblity of us spending our "extra" time spending money, whereas now there's no possibility of us spending money in line (yet

).
Also, if the final version of FP+ continues to discourage park hopping, our February trip will be the last trip we buy hoppers for. What's the point? We can coordinate our dining where we want to be, or just eat at resorts. So with our family, Disney is losing out on potential impulse spending as well as park hoppers. I don't think we're unique when it comes to touring styles. Is being able to track 3 attractions guests select for each day worth the money they will lose out on because of the restrictions they've placed? Only Disney can say, but as an outsider it makes little sense to me. That's ignoring the potential damage this system could do to guest satisfaction, however that's not as concrete.
It hurts the casual guest, they either miss out on desirable times by not being aware of the ability to book in advance or they figure out the booking window, but don't want to have a rigid schedule for a vacation. It hurts the planners, as we were the ones who made good use of the FP- system and received far more benefits than the FP+ system is offering. It theoretically hurts Disney $$ wise, unless it increases bookings. After typing this long, drawn out post I sit here wondering, who does this really benefit?
P.S. What are the chances some of this gets improved by February?
ETA: I guess I should answer the actual question OP asked. Ultimately, 3 would be doable if there were no restrictions placed. Still low for parks like MK, but it would go a long way to making FP+ more desirable. I would also like to see some sort of solution for park hopping, as well as getting same day FP subject to availability. I would love to see the ability to book for example, TSMM and ToT for the morning in DHS and Soarin' at night to use after dinner in Epcot. 3 is definitely manageable without restrictions, 4 or 5 is better but I would rather see restrictions eliminated first.