I went from single to progressive to turret
I started in 1975 with RCBS Jr (then traded for a RockChucker) and loading 50 rounds an hour for a few years. Then I got a couple of Lee Pro-1000 presses. Upped my production to 100 per hour (bought used, no case collator and I never got used to monitoring multiple simultaneous operations, which slowed me down considerably).
Last year I got a Lee Classic Turret (Lee makes the only turret presses on the market with automatic indexing) and I couldn't be happier. (But I do still have the RockChucker.)
It is completely natural operating in continuous mode (like a progressive, taking each round from fired case to finished round before starting on the next cartridge) and also can load in batch mode just as if it were a single stage. The first time out, I loaded 100 rounds in 47 minutes (which included filling the primer tray and powder measure). Caliber swaps take about 30 seconds and that includes getting up and going to the box with the other dies (if I have the powder measure already set on the die; add another minute to mount the measure if I have to do that).
The suggestion to keep your Dillon is a good one unless you have someone who wants to give you a really good price for it. The Lee Classic Turret is very easy to set up, keep adjusted and clean, but the Dillon has probably spoiled you in its output capacity. The Lee's auto-indexing does make it CONSIDERABLY faster than any other turret on the market, but it is no progressive. However handy the screw-in turret handle is on the T-7, it is no competition for the Lee's auto-indexing. These are the reasons I recommend it over the T-7 (unless you really need more than 4 die stations or the extra leverage). Spare turret heads only cost about $10 (though, if you only load two calibers, you might not need a spare). I load for a half-dozen calibers and have a turret for each. The Lee is smaller and lighter, so if you put it away after a loading session (as I do) it will take up less space. Everything I use fits into 3 medium-small toolboxes.
Good luck,
Lost Sheep
p.s. If you do decide to go for the Lee Turret, check out Kempf's Gun Shop. They have a nice kit that includes dies, powder measure and primer feed, but does not make you take a scale. Since you must already have one, that is a plus for you. The Lee dies with powder measure are a natural fit for use on the Lee Turret, so getting them is advisable, in my opinion. $210 and you get a half-dozen MTM plastic ammo boxes, too.
p.p.s. The Lee Classic Turret is far superior to the Lee Deluxe Turret, though each will do the same job. The Classic has a taller opening and handles spent primers better, plus is made of cast iron instead of aluminum.