Update: It's done now (bottled a week ago). I haven't gotten external opinions on it yet but I think it turned out a good beer, but you probably wouldn't be able to pinpoint tea as an ingredient if you didn't know. It probably does give a bit of extra depth of flavour, but it's not distinctly tea-like. I'm saving the last bottle of my 1st batch to do a side-by-side comparison with this, ideally with someone else who would be big into beer.

Next time I do a tea beer I'll probably use 10 g/l and let it steep for longer, maybe till the end of cooling. Maybe to be on the safe side I should tone down the bittering hops to compensate. I wish I knew how to account for the tea's bitterness in the IBU calculation.

yea both. I was tempted to use only tea for bittering but figured I'd try something safer first for a few reasons.

1. It's hard to find information about how much tea to use to get an appropriate level of taste and bitterness.
2. Virtually all of the english-language sources ^(seeing as I'm nowhere close to fluency in chinese or any other language that might have more sources available on this topic)^ I could find online were using both.
3. Since the recipe it's based on was such a success I figure even if you can't really taste the tea in this, it should still turn out good. The only other change I made was replacing the yeast strain (I tried to pick a similar but cheaper yeast this time around). Though it's also possible that eg. my temperature control during the mash the first time around was poor enough to have an impact, since that one was my first own brew ever.
4. I'm not doing micro-brews at this point (am using a 25 liter pot) so I don't want to risk making an undrinkable batch if I can help it.

I only have one fermentation vessel and I'll be making a stout next (looking forward to that, I have it planned out already) but after that I'll take into consideration the outcome of this brew for my next tea beer. I'll be bottling it in just a few days here I think.