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)