It sounds like what happened to me, so I hope my little experience will be helpful to you
I did 1300 kanji in rtk (the 1000 in rtk lite plus 300 other from genki), then I mined Genki I and II, and part of IAIJ, and it was great. Then I started the Core10k madness, and it was so overwelming to review vocabs each day that I ditched my RtK deck, convinced that the vocab deck would have taken care of kanji too. I was doing core10k in standard order and there were many words with kanji which were new to me. It was so stressful I ended up hating japanese and one day I ditched even the core10k deck, because I was reviewing it in a similar way as you do... I started to hit "difficult" instead of "again", and to evaluate reading only and not the meaning of the word (what's the meaning of doing this? xD ). One of the problem was that I was adding tot card every day with the goal in mind to hit like 10k words in a year because those famous fluent people said to do so xD
Honestly at the time japanese was like my only reason to live and what happened caused on me a big stress and depression ._.
But after four months I wrote here on this forum and the users here (I think even you helped me in that thread) gave me great suggestion, so I decided to start from scratch with RtK but after a first time of vanilla I followed some suggestion here and switched to recognition with kanji on front and "meaning" plus "readings" on back of the cards.
For example on front I have this on front:
便
1 - 2 <---number of kunyomi and onyomi
(便り ) <---hidden hint field
(便利 - 郵便 ) <--- hidden hint field
and on back i have:
便り たより letter, correspondence;
便利 べんり convenience;
郵便 ゆうびん mail service, postal mail;
convenience <--- meaning
------
So when I see 便 I say first anything which would identify the kanji, like "convenience" or "the kanji of tayo.ri" and then I say a word for each onyomi (kunyomi is optional and is here more for passive exposition but I end up saying the kunyomi too more time than not), like "ben of benri and bin of youbin".
Honestly even if I know many users here say that to review onyomi by themselves is not useful I think this is what helped me the most.
Now I don't even have a vocabulary deck and I restarted just some days ago to read zero no tsukaima and knowing the onyomi helps me to assimilate the new words more easily, even for kanji which have more than one onyomi, where obviously I can not predict it... it suffices a dictionary check to memorize the pronounciation of the word.
For example in a thread title on this forum there I said a word I don't know:
"地獄"
Now, I know both kanji, the first has two common onyomi and the second has one. Even if I checked it only one time five days ago, I can remember easily it reads jigoku and even the meaning sticks easily. Now, obviously if I don't see it again in months I could forget it, so I plan to do a vocabulary deck but only for words like this, and not to learn new words like crazy and end up reviewing words I don't even knew well the first time I added them just because I feel I must add x words a day.
Another example:
水着
when I saw it the first time I thinked "suichaku" but with some reservation because so many time 着 uses the kunyomi. Now I still remember the reading even if it's not the standard on + on, and the meaning, without any need of ankying the word.
On the countrary when I was counting on words to learn onyomi it was very frustrating because it happened things like this: I saw 絶対 and obviously I was able to read the word, but when I saw 絶 on another word I was unable to remember what was the reading and this made learning words much harder. Now when I see 絶 I know it as "zetsu of zettai" so when I see new words with this kanji it is easier to learn the new word.
Even when words compounds use kunyomi is easier to learn the compound because I know the kunyomi as something pertaining to the kanji itself so even if I see the kanji alone I'm able to recall at least one word with its kunyomi.
Note that this is not equal to reviewing or learning kanji readings "in isolation", because when I see the kanji I don't say "onyomi = ben, bin" but I say an actual word which use the onyomi.
So what helped me was:
1) swich to recognition only kanji deck (I still think writing is useful even in recognition and I plan to do it someday but not for now);
2) review onyomi (and some kunyomi, but if already know a word for it it's a painless process);
3) (todo) rely on native material to learn new words and put them on vocab deck only for long term retention and only if I feel I need to (in other word I don't plan to add words like watashi or kanojo);
as I started recently I have from 60 to 100 kanji to review every day and it requires only 15 mins on the morning. The rest of the day is just exposition to native media and word meanings seem to stick easily by just reading native materials (sort of like it happens with english learning, no need to anki, just read a lot) now that I'm able to recognize easily the kanji and to learn easily the pronounciation of the words I encounter.
I don't know if it would be of any help for you and sorry for the length! I started with this method after the suggestion of a japanese person on lang-8: "to learn kanji just learn a word for each reading".
Now I'm about to start a vocab deck from scratch but at my own pace and only with words I encounter in native material because before it was "oh, anki review has been so stressful today, enough japanese for today!" and now it is "native media first, and anki just as a conseguence".
I don't know if it will makes sense to you, I know everyone is different in learning but still I hope this will help with your motivation because I was in a sort of suicidal state and now I love japanese again and I feel I'm learning much more than before even if I used to do 50 new words a day ._.
