a crash chill at the end of fermentation is an optional process. Its not Necessary, but can help in clearing the beer a little quicker prior to draining/racking off. but time and gravity will achieve the same level of clarity anyway ..
NIce plan, however i would make a couple of suggestions, static rigid plumbing may not be what you had planned, but if it is it can be a pita to fully drain between brews, i would suggest considering using flexible hose to plumb up the varoise aspects. as you only use a few hoses at one time you may discover you only need 2, perhaps 3 x lengths of flexible hose in total. Thick walled platinum cured silicone tube is great, it wont kink or soften with high temp liquor pumped/flowing through it..
Secondly an stc1000 type controller is useless when applied to a boil kettle, the actual boil temperature will change from brew to brew dependent on the TDS and gravity of each brew and will also shift during the boil as vapour escapes and the concentration increases. The temp sensor may provide some interesting info regarding actual boil off temps but little else. a power controller can be employed to apply more or less electric power to elements to stabalise a boil off rate.
Suiatably rated Triacs are high power 'dimmer switches' suitable for elements, or you can buy small transistor based power controllers from ebay, my preference however is to employ a resistance controlled ssr, unlike the dc driven ssrs employed with pids and the such like, the resistance controlled variant lets you simply hook up a dial potentiometer (electric guitar control knob/ 500k ohm linear potentiometer) accross its 2 x control terminals which allows you to dial up and down the actual power the ssr will release over its load terminals. add a heatsink, and a ebay 240v ac amp/volt meter and you can box up a power controller suitable to turn up and down an electric element for less than ��ã10-15 (pre brexit prices)
http://www.ebay.co.uk/itm/SSR-40VA-...730123?hash=item41b01f85cb:g:yIIAAOSw-itXqJd3
http://www.ebay.co.uk/itm/1K-1M-ohm...hash=item27beb24d17:m:m8lVZ4hvJCHBNbD1RCYU0PQ
http://www.ebay.co.uk/itm/Digital-L...001714&hash=item3ad3abb3fe:g:I-YAAOSwA3dYOufP
ebay links are just example not recommended sellers.. (good ad pics..)