The only thing that's good from base is the following : - Gold generation, you literally do nothing and get free gold, if you are an unactive player, this is a blessing, the only reason why you need base level 20
- Factory you will only need level 15 for express item maxing via manufacturing fusion kits
- Not in a hurry ? common with chance of rare also help if you want to save some gold
Maybe it's just me, but i do not trust and find the "chance of legendary" at level 20 factory's worth it, if you want a legendary, you literally craft it yourself with nearly less than half the price for one piece at the factory, or better yet, save for actual tokens and buy packs, the "Legendary from base" for me perhaps is just false hope at an overpriced price tag, the only thing you need from base is 4 gold mines at level 20 and 4 level 15 factories for your items maxing needs.