To me in a way or another you have too many lenses with 35ltd, DA40 and FA50. And sure the last think to do would be to add the FA43 is you don't see at least 2 of the others.
Why ? Simply because the real value of lens is to me linked to the number of shoots you'll make with it, number of keepers and the pleasure of using it. If you have 3 lenses instead of one, each one will be used one third of the time or more likely, the other 2 might not see much use.
I like to go out with 2,3 or 2 primes and take shoots. I like to not change lenses all the time, even if I have a prime. And I like my bag to stay reasonnably light and not to spend to much time looking for the lens I want. I have one lens near 35mm. And that cover all my 35mm needs. I can simply walk a bit and reframe much more easily than changing lenses for such small difference.
It would be really a pain to each time think if I plan to take with me the 35, the 40 or 50 or 2 or 3 or them and then in the field to think that if I had gotten another set it would have better suited the job. And that would be wasted money.
You have currently 3 lenses so you know what you like best and what you like less. You know what you use most often and what don't get used much.
What can I say? If you exchange the 3 for only the FA43, in practice, you'll get everything with one lens. You'll not really miss the f/1.4 because well the FA50 isn't that great at that setting anyway and f/1.4 isn't the most useful apperture. Your border with the FA43 (or FA50) will not be as great as with DA40 or DA35 macro but for landscapes you'll simply stop down to f/8. The only thing you might miss is the quick shift and the macro/proxy mode.
Me I gone DA35 ltd for now because I use the FA77 for portraiture/bokeh shoots. So DA35ltd take care of small objects/macro and landscapes with its great flare resistance, great borders and punchy colors. I don't feel the need to have something in between.
DA35 ltd
In "proxy" mode:
For a landscapes/scenes
But for portraiture or reach, I go for the FA77
To not waste money and to increase fun I prefer to get lenses that do different things than 3 or 4 lenses that almost do the same.