Dungeoneering would be most beneficial because below 69 dungeoneering is quite slow for xp/tokens and you just wanna get 69 asap for real xp. However, it may be hard for you to get going on this today since it's already started and you'll have some trouble finding teams. I'd advise you do a few non-buyable abilities this weekend as it's already too late. Dungeoneering, the only thing you need is very good battle (which you have; I recommend doing temple of sennisten first for soulsplit/turmoil that are immensely helpful in dungeons). Summoning, there's the kyatt/cw tele method that you most likely know.
Training dungeoneering, I had solo flooring for awhile, as it's fairly fast and many teams won't perform your flooring anyway until you get from the teens. So I had solo until you get access to floors in the teens. As soon as you get those floors, complete all of the ones you are able to reset, and attempt w117 to discover teams and do 5 man little rushes(meaning complete asap, do not kill uneeded creatures ( etc) on 5:5 sophistication 6. Every single time you complete all of your open floors, reset(for prestige, that provides more xp) and repeat. Do this until you get access to flooring 20+. After you can do these, begin performing larges at the end(20+) until you are able to do flooring 30(59 dung I believe). After that, do little rushes 1-20/25, then perform large rushes for the rest(still 5:5 complex 6).
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