Ok. I have to start with we moved in January and i can't find the detail sheet for the wine so this is off the top of my head. It is 92 % Barbara pressed not fermented on skins with 8% rubi red for color. I used rc212 yeast and ground American oak in primary with fermaid k. Also added tannin ft rouge and opti red as they recommended. It is from Delicato in cal.
The wine is pretty good. I feel it is missing something on the finish. It has been bulk aging since aug.
Totally subjective.... tannin is an art form using your pallet. The finishing tannin I've been experimenting with is TanCor Grand Cru. I find that using about a teaspoon per 6 gallons adds just a little mid pallet refinement and lengthens the finish. I simply add it to the secondary at for least 6 weeks (more like 6 months).
Words to the wise: don't overdo the tannin and "when in doubt leave it out". I haven't used the liquid tannin additives yet but some people swear by them. Most powder tannins will simply give that astringent "pucker factor". Midwest supplies sells Unico #1 - 3.5 grams for $10 while FVW sells an entire pound of "Wine tannin" powder for $14. So you can see.... this is not a simple question to pose as you have.
I agree with what's been said. I was going to suggest oak,also, as ibglowin said. Remember, oak IS tannin and some oak on this wine might be really nice. A medium french toast will give you some vanilla notes that might be very pleasant.