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)