Around 2 years ago, I remember reading about this famous non-IAP player that manage to rank up many +eggs (over 2500) over at the Puzzle & Dragons Forum. His actual post is in Chinese and on another Chinese forum but hitmantb provided some translation over at the above link.
I thought that play-style was efficient but pretty mundane and true enough, his new 2015 post with updated tips were brought up again at the Puzzle & Dragons Forum and he actually went on to "semi-quit", as translated by sdtzpjt. You can't really gather much from Google Translate as a lot of the words used were "short-forms" or nicknames given to the cards but Kyrdrin did a great job translating most of the tips.
Anyway, I went through the Chinese post again and here are some of the additional things I picked up:
1. He recommends getting all the Magic Stones out of PADW (Japan version) as he thinks it is a failed product and might be removed entirely some day!
2. On getting Tamadras from S-ranks, he mentions that it is possible to get them from coin dungeons. The main takeaway point is to focus on a particular team first so getting additional Tamadras is not actually priority from urgent dungeons.
3. I agree with his assessment of collab REM, personally I think the egg rate is probably equivalent to rolling the normal egg machine without Godfest. His tip on waiting 3 days to roll is basically to guard yourself from making a pull out of impulse; it applies to buying things in general too. However, if you already planned on rolling once, I think there is no harm in doing it immediately as sometimes, you get rewarded unexpectedly like when Gungho did refunds during the recent Christmas Gacha.
Some exceptions to his tips IMO are that Dragon Ball collab leaders are actually quite popular and not difficult to find and I think PAD BT collab is worth more rolls as they are generally good skill-able subs with good awakenings that replace farmable ones. Generally, collab cards are easily replaceable so you don't really have to get them.
4e. On choosing gift dungeons, I think for fruit dragons and late bloomer dragons, there is merit in choosing for the most suitable colour for your main team, especially fruit dragons as they are only available from the egg machine.
5. While he was "semi-quitting", he only logged in to play the urgent dungeons and collect stones from mail so that is something to consider for casual players.
8. He made an update to this section and mentions about the pal points you gain from having more friends, resulting in more pulls for rare materials in the Pal Egg Machine. For him, it didn't matter as much because he has no shortage of materials, probably due to him having enough boxes to store extras from farming. He does say that increasing friend space is equivalent to spending on box space which only brings benefit with no draw-backs, and definitely better than spending on rolling the rare egg machine.
9., 10. & 11. are generally good tips on skill-ups and Piis. For tip 11, he does list out some examples in a FAQ:
- Hero gods' and Chinese gods' skill-up without their own survey dungeons are worth it. With that said, they are coming from survey dungeons eventually IMO, so I would only do it if that particular Hero/Chinese god is in my main teams.
- Red Odin's skill-up is in a dungeon where there are many useful drops so he doesn't use Piis as it is worth running multiple times.
- He does find the box space and stamina required to evolve for skill-ups to be not worth the effort for skilling up Haku so he justify feeding Piis. I think this is the case for most cards with skill ups that require evolving.
13. Good tips about the coin dungeons.
14. He does brought up some interesting observation about the introduction of new cards; the rate of introducing new cards have increased as compared to previous years. Another point is that the god cards introduced starting from the Hero gods series require specific REM subs to function better. I think a lot had to do with the awakenings adding another layer of decision in team-building. It also result in a continuos chase for cards in rare egg machine. E.g. You rolled a Light Kali and now you want a Fuma for sub, or you got Pandora and now you want Hanzo for sub.
He goes on to say that it is difficult to build a perfect team so do not try to copy others or aim for that. It requires a lot of luck to get the same colour and right type from the rare egg machine so just form the best team possible from your rolls and +egg them. There are also many powerful non-REM ultimate evolved descend god leaders like Athena, Beezlebub and Satan that are very usable which I totally agree on, especially Beezlebub.
His closing words were to try to strike a balance with ranking, farming +eggs, improving your skills, levelling your cards as well as rolling the rare egg machine (he previously recommends 1-2 pulls per Godfest but the lack of interesting cards led to his "semi-retirement"). Most importantly, enjoy the game and have fun!