One thing i like to do is beyond every time i get a beyond or sea witches map with decent quantity. Double beyond is really fun for xp/mobs but won't increase your map drops. also if you are using an inspired learning it gets pretty insane. It is very well made and a couple of people in the U4GM.com office have made use of it and now their characters are able to take a lot more damage as a result.

If you just have 400c you could also consider getting a few sextants and then just applying as you need to maps. like for example if i roll some maps and get bloodlines&nemesis I will try to get some sextants on the map to add mobs since nemesis/bloodlines are a more multiplier but don't really add mobs. Beyond/bloodlines work the same way in that you need mobs in the first place. Some of the other zana mods will always give you guaranteed monsters instead or gambling opportunities (perandus, harbinger).

It's mostly enjoyment and xp. You get card and item drops but not maps from beyond mobs. There are also things you can do with nemesis monsters drop additional currency sextabt but usually i just do it because it adds a tonne of mobs to your map and if you get a breach/abyss it is insanity. The way double beyond works is they will scale eachothers beyond portals. So if you kill a blue pack and beyond mod 1 spawns 3 beyond dudes and you kill those, beyond mod 2 can spawn mobs off of the initial and the beyond mod 1 monsters you just killed and vice versa if that makes sense.

If you have a headhunter or inspired learning a lot of beyond mobs spawn as rares and it juices you up pretty hard. Same thing can be said for esh shield and kb/ other on kill buffs. Let us know what you think of these suggestions and be sure to check out our Path Of Exile Currency Hot Sale and grab yourself some POE buy Currency at a crazy low price.