[HomeBrew] Universal Interface - Comments Or Suggestions?

[Brian Short]

I am going to build an interface for my computer sound card
and HF radios.  I am familiar with the basics and have done
some initial research, but would like to make it as convenient
and flexible as possible.

My uses for such an interface are:

Writelog -
   CW w/PTT output
   RTTY w/FSK keying
MMSSTV
   Rcv, Xmt
   PTT
MixW and/or other PSK31 etc software
   Rcv, Xmt
   PTT
Radio Control (with same COM port)
   FT-1000MP
   IC-706MkII

My plan is to utilize isolation transformers which I
have from a surplus board (nice Stancor components)
for both sound card input and output, left and right.

For the Yaesu, I will have a pad for MIC level (transmit).
The Icom requires line level.

For PTT and CW I would prefer to use opto-isolators.

For radio control, the 1000mp interfaces at RS-232 levels.
The '706 requires a TTL level converter which I was
thinking would be done with a MAX-232.

I already have a working SSTV etc system going, but
would like to make a convenient solution for multiple
uses.

Ideas?  Lessons learned?

--
73, Brian
http://members.cox.net/bshort4/