Some of the copper reds I use are pretty thick.
I have noted a couple of things about wax emulsion.
1. The thicker the layer the harder to dry fully and properly. Any water based coating is going to have this problem. Since moving to hot and dry Colorado things have improved significantly. If you live in humid Florida (as I did), you are always going to have problems.!
2. Both thin and thick layers can form rougher surfaces (either because of brushing issues with thick emulsion, or roughness of the bisque with thin layers). This automatically prevents good repulsion of the glaze.
Hot wax works by cooling rather than evaporation so is always going to "cure" better, and faster. Generally it also has a smoother surface which helps repel the glaze better. The downside is that it cools very fast and is hard to handle. Frankly I've also seen hot wax have problems repelling the glaze if it's not applied smoothly.
There are three routes of investigation that occur to me.
1. Find some sort of coating that does not rely on evaporation. Either a very thin two part epoxy or a coating that relies on oxidation (some of the polyurethanes work this way). This probably doesn't much fix your speed issue. You also want something that is high enough gloss to really repel water.
2. A coating that uses more volatile compounds to dry. Shellac is an example although as LT notes, this apparently is susceptible to water damage and therefore doesn't repel water very well. Some of the modern lacquers can be diluted with acetone and dry very fast and are more water repellent. Acetone etc has a very very low surface tension and I could see it not keeping a tight enough line.
3. If we focus on the water repelling properties, there are some very high tech water repelling silicones that might do a better job than even hot wax. Obviously silicone caulks spring to mind but probably aren't suitable for your application (mostly because of viscosity). But there are also silicone concrete sealers and fabric sealers than might work really well (I'm pretty sure I've seen very tight water beads on coated wood and concrete). These tend to have longer drying times, but you might find something that really repels the glaze.
I use 100ml syringes for measuring specific gravities and the glaze will degrade the plastic and rubber plunger so it's almost impossible to move. However a single coat of silicone leather protectant completely renews it and I've noticed the glaze, however thick, really beads up nicely.