Strings for Guild D35 NT acoustic

I have a 1970 Guild D35 NT acoustic and am looking for advice on which brand, type and gauge of strings to use. I'm only using it for recording using a microphone - no pickup. I'm mostly recording acoustic guitar as a track(s) with electric guitar, keys, bass, etc., so I guess I'm striving for a good bright cutting sound with the higher strings more than I'm going for a full tone with lots of bottom. I know Guilds have a reputation for having a lot of bottom but this one doesn't have as much of that as some others.
It would be nice to have a string that retained it's brightness longer - I tried a set of D'Addario strings and they went dead very quickly. I'm really a bass player and there's so many options for strings that it's a little overwhelming. Are the coated strings any good?

One other question about this guitar - I had it setup by a good repairman in my area and he replaced the nut and bridge saddle with ones made of bone. I think he put medium gauge strings on but I can't remember which brand. The guitar sounds great but the "D" string is buzzing a little on the 1st through 4th frets, which is really irritating when trying to record. The buzzing makes it sound like the mic is distorting or something. What I'm wondering is if I go with a light or medium light gauge of strings and loosen the truss rod a little could that make the buzzing go away or should
I be thinking of going heavier and tightening the truss rod. I'd hate to go heavier because it already feels pretty stiff now and the sound is great.

All opinions are highly welcome and thanks in advance.

I just remembered - the strings the repairman put on were D'Aquisto. I'm pretty sure they were medium gauge but they could have been medium light. I like them much better than the D'Addario strings because they lasted longer.
If I could only get rid of this buzz....