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)