I have the 8.1 ratio and love it.  What upgrades do I need to make this reel throw lighter lures? 

how light?

Define lighter. Are we talking under 3/8 oz? 1/4 oz? Down around 1/8 oz? If you're looking at a spool upgrade, you should just purchase the T3 1016. A bearing upgrade would cost $20-40 in addition to the cost of the tool to take the Daiwa spool pin out or sending it off to someone to perform the upgrade. 

 

These upgrades I'm about to list won't help with the casting but they will improve the overall feel of the reel. The Ballistic's handle is sort of lousy and cannot receive additional bearings. Look for a handle upgrade, either a carbon fiber from Hawgtech or a four bearing Daiwa handle. I have two Hawg Handles and I recommend the 94mm straight handle with the cork knobs. Additionally, Carbontex drag washers and a bearing in place of the worm shaft bushing are cheap and very nice quality of life improvements. 

If you want to throw light baits, I recommend the SV1000 spool. Other options would be the RCS1012 or the Megabass 1010 spool, though those are more expensive and harder to procure. The SV1000 spool is about 90 bucks, it will completely transform the reel.

I have never used that reel, I have all Shimanos. But like Cgrinder said, do yourself a favor and pick up one of those Hawgtech handles. I have one with cork knobs on my Scorpion 1500XT, and it is amazing how smooth and light that handle is. Makes it feel like a totally different reel!

Like Tywithay said the SV spool.  $80-90.  The 1016 (stock T3) spool is nice and found for around $50 used fairly frequently.  As is the stock T3B spool will toss 5/16oz + pretty well if you get the reel adjusted properly. 

 

The Stock bearings in the T3B are nice enough once you clean and lube them.  My STOCK T3B (just cleaned and lubed) cast just a bit shorter than my tuned Zillion with shieldless orange seals and a 100m spool...  IF you do upgrade spool bearing I strongly recommend the stainless ABEC 5 from Boca (less than $20).

 

The 8:1 Ballistic has a nicer handle than the 6:1 and 7:1.  It's basically a Tatula handle with Lexa knobs and a bearing under each (with one bushing as well).  BUT the knobs are riveted on, so no go on adding another bearing.  That being said the stock handle is absolutely fine and you will probably not notice any difference swaping it out, aside from some Bling/Swag.  You can't help yourself and have to have 4 bearings, Lexa assemblies (knobs/handle/bearings) are $20 from Daiwa (back ordered to JUNE)  Tatula assemblies are $29.

 

Inside the reel, you can add 2 bearings.  One to the Levelwind (5x8x3) and another below the driveshaft (5x9x3), these are very low rotation parts and an Abec1-3 is fine.  These are a couple bucks each (or less if you know where to look).  They just add a bit of smoothness to the reel, again not a huge or even medium preformance enhancement.  If you are tearing the reel down this winter to clean it, do this upgrade at that time.

 

If you get bit by the weight weenie bug the aluminum drive shaft from the T3 (1016) is $20 and will swap right into the T3B.  Saves about 1/2 oz.