upsides to making a portal to heaven  
   to   build   the   factory  there    
  
                                          
 first  of all, real  estate:  the highly 
 fractalized  geometry  (not  proven  but 
 likely  to be the case)  implies  almost 
 unlimited room; even if the portal  tech 
 would  be  stolen,  chances  of  running 
 into a  competitor  is  close  to  none, 
                                          
 secondly,  the  resources:  heavens  own 
 alchemical   properties  (proof  exist!) 
 makes  most  base  materials easily  and 
 readily  available.  once the  molecular 
 movement  patterns are  mapped out,  any 
 compound   can  be   created   virtually 
 without                            cost. 
                                          
                                          
  
   downsides to  making  a  portal  to  
  heaven to  build the factory  there   
  
                                          
 current  portal tech takes  some  energy 
 to hold  open, which isn't a  problem in 
 itself. test  results however  has shown 
 that without  an active tether, heaven's 
 time  flow breaks  down completely. even 
 a  momentary  fluctuation of the  portal 
 would    render   all   remote    assets 
 practically  lost.  much  care  must  be 
 taken  to  maintain   portal  stability. 
 (one option  could  be  several portals)