Well, the Mangler mostly does the same stuff as every other multi-FX unit from the modern era, much like the Eclipse you have there. Except for a few programs that aren't really musical in the traditional sense, like ringmod and that weird pitcher stuff that Kurzweil was doing. But yeah, if you're looking to add another cheaper unit that can do a variety of stuff I would also look at the Ensoniq DP/Pro and the Sony DPS V77. Great units, but mostly overlooked.
And if you want something really cool that's both a traditional dual/stereo digital delay and a lot more, check out the Symetrix 606.