Any way to get use out of Intel on higher difficulties?

[CommodoreGray]

i play mostly UDM3.0.dc
On impossible I only get to sabotage when i have like 50+ systems and they have only a few left. They get big bonuses so don't expect your offensive intel to work; it does work however in preventing them sabotaging you.
And like Thunder said, you need more than 30k intel; i had games as Romulan with 30K+ intel and 200%+ bonuses and still limited success in sabotaging. But they don't sabotage me anymore or if they get lucky it's just a minor effect.

I've never played UDM, but doesn't is use higher populations per system and a bigger map? I imagine in my closer to vanilla game the needed Intel would be lower.

Defensively I haven't had serious Intel problems since I fixed the bug with the Intel bonuses always acting as if 100% was dedicated to the area.

As to allocation, when i meet a major i use 1 to espionage and up to 10 on sabotage. Don't leave it 0.
Sometimes if i plan to befriend the klingons i leave it at 0-0 against them; but i follow that with not colonizing or building outposts or member-ing minors near them and with waging war and intel war on their enemies; with patience you can get them as allies.

I do the 1% thing too.
The Klingons are definitely nice friends. They're annoying to fight, they're less backstabbing than some others, and they're poor so you can hurl cash at them more easily to keep them happy. I'm never actually had an major sing a full Alliance I propose, though; only ones they send. But an Affiliation is very nearly as good in most ways, and you can buy those with enough money.

About building intel, don't neglect it even before you meet a major; build and man your intel main structures; they accumulate like an intel buffer which will protect you in the first turns after meeting a major; think of it as the shields of a ship; but they will drain it and then you get sabotaged; but that buffer gives you some turns when your intel might try something against them and even if you have missed it prompts them to reallocate some of their intel to defense instead of attacking you.

I started stocking my Intel centers from day one when I read it creates a stockpile. It prevents a nasty surprise when you make first contact with the Cardassians.

I do wonder, though, if the stockpile is a huge part of the issue. The Cardassians seem to be the only AI empire that does too much offensive Intel (even the Romulans mostly seemed to coast by on the old bug), and they often do poorly and don't get too many systems. So the game goes on with everyone mostly using Internal security and as a result, all build a big stockpile of security. In fact, my current game is the Klingons on Impossible and I'e had good intel results against both the Ferengi and the Cardassians by throwing 50% at them as soon as we started fighting; presumably they simply haven't had time to build a defensive stockpile before my attacks hit.

And there is a patch out there that when you conquer worlds from a major it keeps the intel buildings(and the sopecial buildings); since intel does not depend on morale, manning those conquered intel buildings is very "profitable".
Here's the link on how to install the "keep intel buildings when conquering":
viewtopic.php?f=294&t=3115

I know about the patch, but I don't use it since I think it makes sense that espionage centers are destroyed (also, since the morale issue you mentioned exists it would make it a bit too tempting to use conquered systems as mass spy networks!).