You can randomise text messages with sh3 commander which I think you already know but I do not think you can trigger area specific messages.
You can however set by year.
I have already done a sloppy job at some of mine but just wanted to see how it worked, I am thinking of adding lots of reasons why the men wont run the engines because they are tired etc etc.
[0_data\Menu\en_menu.txt]
ChooseFrom=13
RndMidPat=1
0_STRINGS|4198=Keep up the good work Kaleun!
1_STRINGS|4198=Great stuff Kaleun!
2_STRINGS|4198=Very impressive!
3_STRINGS|4198=Happy Hunting
4_STRINGS|4198=Look Forward to seeing you back at base!
5_STRINGS|4198=Great stuff Kaleun!
6_STRINGS|4198=Very impressive!
7_STRINGS|4198=Happy Hunting
8_STRINGS|4198=Keep up the good work Kaleun!
9_STRINGS|4198=Great stuff Kaleun!
10_STRINGS|4198=Very impressive!
11_STRINGS|4198=You are doing well
[1_data\Menu\en_menu.txt]
ChooseFrom=6
RndMidPat=1
0_STRINGS|514=I hope she holds!
1_STRINGS|514=Standbye for leaking!
2_STRINGS|514=The men are getting uneasy!
3_STRINGS|514=Do you want me to level off captain?
4_STRINGS|514=I don't think she will hold the pressure!
[2_data\Menu\en_menu.txt]
ChooseFrom=6
RndMidPat=1
0_STRINGS|515=We have never been this deep before!
1_STRINGS|515=Suggest we rise a little SIR!
2_STRINGS|515=The men are nervous Sir!
3_STRINGS|515=I think we should level off?
4_STRINGS|515=The pressure will get us soon!
[3_data\Menu\en_menu.txt]
ChooseFrom=3
RndMidPat=1
0_STRINGS|598=Enemy is pinging us, sir!
1_STRINGS|598=Those Bastards!
2_STRINGS|598=Were being pinged!
[4_data\Menu\en_menu.txt]
ChooseFrom=3
RndMidPat=1
0_STRINGS|599=Enemy ship engaging us, sir!
1_STRINGS|599=There comming for us!
2_STRINGS|599=What shall we do Sir?
[5_data\Menu\en_menu.txt]
ChooseFrom=3
RndMidPat=1
0_STRINGS|601=We may have been detected, sir!
1_STRINGS|601=Damn they have detected us, sir!
2_STRINGS|601=I think they have detected us!
|