Well both of those are relative phrases. "Spools quickly" relative to what? Nothing you will look at will spool faster than a TD04-13T. Sucker reaches boost at like 2k RPM on a good tune. Same goes for top end. If you size the turbo to be so big that it makes max boost at, say, 6500RPM, it's going to not make any boost till 5000 RPM or higher.
Personally what I think about is area under the curve. The earlier the turbo generates torque the better but not if torque falls off at higher RPMs. This leads you to a turbo that is what some would call "undersized" but which is large enough to maintain efficiency all the way to redline. You'll actually be below the maximum boost level throughout. After all, if you hit that in the first place, it's inherent that at any lesser RPM, you're still in some degree of lag.
For explanation purposes, here's a dyno graph of my EJ257 with a TD05-16G (regular, "small", etc). Note torque is the top black line and boost is the green line.
Note the slope of the torque curve. The car spools very quickly (it's already at 4PSI where the graph starts at 2.5k RPM) but tops out pretty early. Peak Torque only lasts till 4500RPM. The ideal shape, in my very biased opinion, is one where the peak torque lasts till just before redline. With the shape in mind, you can be a little bit more subjective about what size turbo you think is ideal. Note though that we haven't mentioned target boost or hp/tq levels. If your concern is sizing, these are independent. I would also point to the RPM difference between gears. This gives a rough outline as to the min and max RPM points you should concern yourself with. For instance the gap between redline third and fourth gear (for a constant whatever speed that is) is probably a good measuring stick. You care about torque over that range plus a bit probably. Point is you don't care about power at 600 RPMs.
Note that the EJ257 will spool a little quicker than the EJ255 due to an improved top end. Also the redline is 250-500RPMs further out. This effectively means you'll want a slightly smaller turbo than the EJ257 would.
It's hard to speculate exactly what turbo will give you a given curve just like it is to speculate about what the peak numbers will be but I think the TD05 is probably the right housing. A large 16G is an appealing solution but will probably have some torque falloff, especially with a good 93 octane tune. The 20G will probably hold max torque pretty close to redline but will take longer to spool. The 18G is probably "just right" IMHO.
I'm not the originator of this table but I find it helpful:
TD05 16G E3 - EJ205
TD05 18G - EJ255
TD05 20G - EJ257
Go up a level if you want more power at the expense of spool and down a level if you want more response. The TD04-19T is probably a more efficient equivalent of a TD05-16G