The combo is what it is.

Minimizing exposure and development may help.

Switching up to medium format will help. Similarly getting closer to your subject may help, say head and shoulders portraits instead of full length, helps make subject details more prominent than grain.

Switching to Delta 400 or TMY or TX or back to FP4 may help you refine your results too.

But, part of the 'age' or look or feel or whatever you want to call it is the grain. And, nice sharp grain actually helps photos look sharper.

Everything in the system affects the perceived graininess. Lighting, lens contrast, flare, how its printed...

My advice though, before you change anything, is to put the print on the wall (thumbtack or frame) above the sofa, get back off the sofa and with your feet on the floor and standing up straight look at the print and ask yourself does it look good? Leave it there for a week. If the grain still bothers you after a week, try one of the fixes above.