If you are pulling "near perfect taste" then don't change a thing and just enjoy your coffee.
The "100%" shot is what people call "the God Shot." (Originally, the God Shot was defined as having to be a
double ristretto, but these days the term has to some degree become more generic than that and is used to refer to the absolute perfect shot of any type.) For me, the God Shot is very rare. Most shots I pull at home are "85% shots," and this is with several decades of experience, the highest quality water and coffee, very good equipment, etc.
This morning, I had two double ristrettos. The first I would rate at about 75%, the second was 80%. I don't worry about it. Both coffees this morning were very good and I enjoyed both the coffee and the experience. That's what counts.
Taking your shots from 60% to 70% is relatively easy; making the move from 85% to 87% on a consistent basis is very difficult, and many times comes down to random chance.
For me, the quality of the taste is important mostly because it enhances something else; my enjoyment of the process of preparing it, my conversation with friends, my enjoyment of the newspaper, the "coffee geek" inside; whatever. That is more important than the "mere" taste itself.
It sounds like you are 70% or 75% of the way to being where you want to be: pulling "very good" shots on a consistent basis, and having fun doing it. Focus on rounding out your kit; the tamper is a key part of keeping things consistent (which is your goal and something you should fixate over). You can spend a lot, but you don't need to. Something like
this will work just fine and it could be many years before you feel the need to upgrade. Or, you can spend more now. Up to you, but that Rattleware will be just fine.
I agree with Shrink; take another look at your basket before you order something.
Once you have your equipment rounded out and you are more or less pulling consistent shots at about the "80% level," then you will begin a process of identifying the weakest link in your chain and focusing on improving just that one thing, holding everything else constant. For many, once you have the grind roughed in and your kit rounded out (including high quality water and coffee), the weakest link will be micro-adjustments to your grind or the quality of your tamp and puck. You will improve that weakest link and then move on to something else. Eventually, you will have "fixed" so many weakest links that something you "fixed" years ago will again become the weakest link and you will start to work on whatever it is again. Eventually, you will obsess over whether you should be pre-heating the brew head with 2 oz of water, or 2.5. Right now, that difference would not impact the quality of your shot. Eventually, it will, and you will decide whether you care or not (either is ok). Your scale will change; what used to be an 80% shot for you will suddenly be a 60% shot. You will decide whether you care or not. Again, either is ok.
My advice is to buy a tamper and scale and then just enjoy yourself for a while, content in the knowledge that you are producing better coffee than you could buy in 80%-90% of the coffee shops in the US, and focus on improving your skills. Weigh and time every shot, keep notes, try some different coffees, and don't worry about chasing the God Shot for a while. It will happen, and when it does you will re-think everything you are doing and rush out and buy new equipment (and probably a roaster), consider moving to Italy, and slowly let the God Shot creep in and take over your soul. I've had one dozen God Shots, in 30 years, almost none of which I produced myself, and I cherish the memory of every one; but the richest parts of the memories are who I was with and where I was.
Congratulations on making your shots so far; enjoy them.
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I have been meaning to look. Thank you for the link.
