Diversified Portfolio is definitely not for every deck, mostly because of its 1 cost. Let's compare it to what I feel are its closes neighbors, Beanstalk Royalties and Sweeps Week.
Versus Beanstalk Royalties:
- BR is 0 to play, and can be played right after an Account Siphon drains you of your final credit.
- To give an equal net credit profit to BR, you need to have 4 remote servers, and then it's still worse than BR due to the point above.
- DP does cost less influence to use outside of Weyland.
- BR is far more useful early game, as you won't have that many remotes up until later on, if ever.
Versus Sweeps Week:
- Both are contingent credit gain, though they have very different criteria. The big difference is, you often have a more control over how many remote servers you have, and less control over the number of cards in a runner's grip.
- DP synergizes with Building a Better World while SW doesn't, for several reasons. First, DP is a transaction, and SW isn't; but frequently more important is the fact that this doesn't cost Weyland any influence to use.
- SW gives you a massive 4 boost if the runner has a full default grip of 5 cards. To match that you need a whopping 5 remotes (unless playing BaBW).
- DP's influence cost is significantly lower at 0, for non-NBN decks.
- SW is amazing on the first turn, while the best DP can usually hope for on the first turn is a measly 1 net gain.
- SW frequently causes runners to keep no more than 4 cards in their grip, and can really hurt those who take advantage of Public Sympathy.
- SW doesn't work well if you do significant brain damage, while DP can still be useful in that situation.
So, what does this all boil down to? Basically, if you're playing Weyland, always take up to 3 Beanstalks before even considering DP. NBN will usually want Sweeps Week over this, especially for its fear factor (including the ability to annoy Public Sympathy runners), and early-game utility. Even in HB, if I can spare any influence, I'd take BR over DP in a heartbeat. So, all that leaves is Jinteki...
Oh, Jinteki! Finally, a faction that can really make use of DP. This definitely isn't for every Jinteki deck, but there is one place this can clean house, and that is shell game white tree. With 5+ remotes not uncommon in those circumstances, this becomes a powerhouse. If you're ballsy enough to leave agendas on the board (even fully advanced), this can become a quick trip to credit heaven late game, and flush out your credit pool when you're still busy piling credits on Shell Corporation, letting you delay grabbing credits off of it for a few turns, which makes it even more efficient! And, finally, it gives runners an incentive to trash exposed traps in remotes, letting you shuffle them back into R&D with Jackson Howard.
That said, this will never shine in the early game, so frequently you'll only drop a single copy in a deck. But, I feel like DP is to shell game RP what Mark Yale is to Titan Transnational—an almost mandatory inclusion, yet used sparsely.