I find configuring my ESI juli@ card to be irritating when the process of selecting the right latency sample rate, dithering and other options have to be configured. As the versions have changed, I have had ongoing problems with the sample rate dropping, etc. My suggestion is an Optomise button for the audio device. A feature similar to those on Windows such as the facility on screen resolution configuration. Possibly a 'best guess' algorithm that would test the card and find the best combination for your particular audio device to simplify setup and operation. The optomise code runs checks for supported sample rates, latency, dithering,etc and you can then choose from a simplified choice of HQ vs latency from it's recommendations.   
Another suggestion (I dont know if it has been suggested previously), would be the facility to select 'New Effect' from the menu as you do with New Instrument. It would be easier than having  to delete first and then go through the menus to select your choice. Also grouping the effects on the menu by type would make it easier to change from one type of effect to another of the same type e.g. delay to delay.

To clarify some of the points I made:
New Instrument should have been 'replace'. It is irritating that you need to first delete the effect / processor then go into the menus and select a new one. If you have a lot of VST's it does become tedious scrolling down, especially if you need to remember what type of FX / processing the name on the list applies to. If they were automatically grouped into folders according to type (I don't know if this is not implemented due is a limitation of Steinbergs VST system) , it would speed up the process of changing within the same type .e.g. digital delay to another digital delay or an analogue delay simulation. On my storage hard drive I group them according to type in folders, so why not have that facility within Sonar? I presume that the .dll file has an ID for type, if not why not push for it's integration for multi- platform support.
 
With the Optomise suggestion, it's KISS. It's a lot quicker and easier for the PC to run checks and find the best settings. Nothing more irritating than stability issues half way through song production! Stability is the reason that I still have a BOSS BR900CD for backup.
 
X1 STUDIO - X1 PRODUCER - X2 PRO - X3 PRO - to SONAR PLATINUM
VST SYNTHS, GUITAR and DRUMS by AAS, Arturia and XLN plus numerous freeware VST's
VST FX various
 
Intel i5 3570K O/C 4.2GHZ
16GB Crucial RAM
512GB SSD, 256GB SSD, 1TB HDD, 3TB USB
ESI JULI@ SOUNDCARD (dedicated for SONAR) + ASUS default card
Focusrite VRM box
Alesis M1 Active 520 USB Monitors
EMU MIDI box
 
3x BEHRINGER MIXERS 12-2FX, 10-2FX and 10-2 USB
6x HARDWARE KEYBOARD SYNTHS
1x HARDWARE SYNTH EXPANDER
3x KORG VOLCA SYNTHS
ALESIS PERCPAD
19" RACK HARDWARE FX and PROCESSORS by BEHRINGER and TC HELICON
2x TC HELICON FLOOR VOCAL PROCESSORS
VARIOUS MICROPHONES dynamic and condenser by AKG, SAMSON and BEHRINGER
Guitar, Bass, Speakers and various hardware effects.
SENNHEISER and AKG HEADPHONES