I am a newbie . . only been shooting BP about 8 years . . and just built my first rifle last year. . so I am learning all the time.
Yet, there are some things I dislike and some things I like, for example, I don't like browned rifles. I like blue or unfinished even if not historically correct.
What I've noticed is that ML shooters are few and far between among gun owners. Most of the time when I show a shooting friend my ML rifle, they have no clue that what they are holding is a late lancaster circa 1780-1790, a Siler lock, davis double trigger etc. Most of the time, its just a long heavy rifle with pretty wood to them.
It sounds as though you know enough about ML's not to ruin one with some silly addition or bad craftsmanship. . .
There's nothing at all "wrong" with a TVM fowler. They make a fine rifle that is highly functional. Is it a museum piece for a historian to critique? The answer is no, but few kits are, in all honesty.
If you really like the TVM Fowler, don't let anyone steer you into something that is just OK. . . your love of your gun is a little like your own child . its beauty is mostly in your eyes. . and you love it because it is yours.
And if you want a rear sight, like a traditional ML rifle would have, go ahead and do it.
BTW - I was just in the new Revolutionary War museum in Yorktown VA last month, and they had an original colonial fowler, circa 1780 built by John Shriver, w an Oct to Round 20 gauge barrel WITH A REAR SIGHT, just like the one on my Lancaster. . .and without the carving it looks fairly similar to the TVM to the average shooter.
That's my two cents.