One thing that slows me down sometimes is making fumbly errors mismatching variable and function names. For example, I might have created a function somewhere else. I type it (and for whatever reason the auto-complete doesn't find the function) but unbeknownst to me forget to add an "s" in e.g. the function GetVariableType(s)
I have to get 3 minutes into running a longer script to hit the BAM misnamed function or variable.
I realize scripting languages are loose in this way which perhaps allows some flexibility and friendliness to non-hardcore-programmers however I think adding simple checks such as "does this function or variable exist somewhere? " would be pretty fast and would save A LOT of time for everyone in the long run. Perhaps even a red underline e.g. as is done for mispelled words in Word, indicating there is no matching function or variable.
I realize this could also be solved by better programming practice as well, however for the level of technical user Smartbear caters to I think this would be a useful feature.