1. Attenuverters
The best thing that happened in recent years. Attenuverters are more flexible than attenuators, because they can do both positive and negative voltages. A very good thing! Ten years ago they were a rarity in Eurorack designs. Nowadays everybody uses attenuverters. They're perfect for playing live. Tip: try the A-133 Polarizer for live playing. Not a 'real' attenuverter, but it's great for modulating.
2. Miniaturization
The Eurorack format is by definition one of the smaller modular formats. The width of modules is measured in HP. The theoretical minimum width of a module is 1HP. We haven't seen any 'real modules' this thin yet, but recently Doepfer, Make Noise, Pittsburgh Modular and Bastl have all launched a 1HP blind panel. In the near future, we expect 1HP expanders, tiny switches, micro sensors etc.
Altho it's a good thing to avoid useless HPs in the Eurorack environment, there's also the aspect of playability. Look at the Qu-bit Electronix EON for example. The mini jacks should work fine in 2HP, the switch too, but look at those knobs. They're made for children, not for adult musicians. The quality of knobs is something you learn to appreciate when you buy an expensive module that has shitty knobs (companies like FLAME and Circuit Abbey come to mind).
A really good knob is a joy forever!
Playability is not just about good knobs, it's also about room to maneuver. The good people at Intellijel learned this the hard way. They redesigned their popular Dixie oscillator (from 4HP to 6HP) to make it easier to use. And while we're naming and shaming, let's mention The Harvestman, who loves to come up with odd HP-sizes, even if you can't turn certain knobs without touching others... and you get a 1HP-hole, a silent witness of the miniaturization craze.
3. Function clutter
Altho it's a good thing to have modules with lots of functions, there's also the aspect of quality. Look at the Qu-bit Electronix EON for example. Sure, this envelope generator can also be an oscillator and a noise source. But is it really the oscillator or the noise you want?
There's a tendency to put more functions in smaller modules. Look at the Disting by Expert Sleepers: "A 16-in-1 multifunction module, offering a variety of CV and audio processes, including a selection of oscillators (LFOs/VCOs) " OK, so you'll need to memorize 16 things. The politically correct terminology for this issue is 'function density'.
Real modular synths don't have menu's!
