Close to my own needs, I think. I'll share what i've found;

Bronica- there are a few lenses for both ETRSi and SQAi that focus
particularly close. If I were you, a 60/105 macro/180mm kit would be my
choice. Slap an AEII/III and Speedgrip on an ETRSi and you'll think you're
using a big 35mm.

Hasselblad- There really aren't any lenses ideal for portrait or macro that
don't need an extension tube, so if you consider 'Blad (or most other
systems) factor a tube price in as well. Again, with the right accessories,
a 'Blad can be very easily handheld. Be careful with which model you choose-
500 series are great but lack certain "home comforts" like TTL flash
metering. A 503 would work well, but having handled a motorised ELX body i'd
recommend against one, as handholding is even more of a pain than with a
Mamiya RB. If you go with the 20*/200* series with focal plane shutters,
you'll have access to faster lenses and built-it AE, but even higher prices.
200* series are older and spares are all but unavailable. 20* series are
ideal, and will work with 500 series lenses and 200* lenses with stop-down
metering.

Mamiya- RB is too heavy and awkward for handholding (the shutter cocking and
wind-on are separate levers). RZ is marginally lighter, shutter cocking and
wind-on are in the same lever, and the whole system is more modern. Either
are ideal for tripod mounted portraits and macro, as i'm sure you're aware
the built-in bellows focusing allows to very close work- put a wideangle on
and you can get lifesize reproduction without tubes. Still a pain to
handhold, though.

The 6, 7 and 7II have *no* close focusing lenses. The 150mm (most people's
first portrait lens) focuses no closer than 6 feet, and any closeup adapters
would mean the rangefinder wouldn't be accurate.

Haven't looked into the Mamiya 645 much, though.

Rollei- similar to Hasselblad, thought with the 6008i there is a built in
handgrip which I think would help out a lot. Again, short tubes for
portraits are a must as most of the lenses are the same spec as Hassy
lenses. Like the 20* series, the 600* series largely have built in AE, but
also have built in motorised advance. Do your research for specifics on
models.

Pentax- the 67 looks like a worthwhile system, though the big instant-return
mirror and big shutter mean vibration is problematic- fast shutter speeds
are a must-have, I think. Lenses mostly fast, tubes are cheap, macro lenses
not uncommon.

 Mamiya 645, reliable, cheap, good optics and can use an adapter to use the
cheap/good P-6 mount optics like the 180mm F2.8 CZJ sonar and the
tilt/shift soviet lenses.

If you wanted to do it on a budget then you could always try the
Pentacon 6TL. If you get a reversal ring you can use the standard 80mm
lens to do macro work. It is maybe too short for potraiture unless you
are doing groups. For landscape you could use the multi-coated version
of the f4 50mm Flektogon. Be very careful how you load the film,
though, or you will get overlaps.