I would look into why its taking an HOUR or 2 per encounter at such a low level. There are some boss encounters that may last that long, but the rest shouldn't. Also the fact that you've all played at least at year and using classes that are more advanced then what KotSF was prepared for, some of the encounters should be pushovers. Being at level 3 now, you should be almost completed with the adventure. It only goes to level 3, so I don't see how this is going to last until April.
It sounds like there is a misunderstanding somewhere.
Yeah, i thought the same thing. Wierd. It's an adventure for lvls 1-3. There are however extensions to the adventure (FR's version and extra pre-enter the keep encounters) but they aren't that much of an extension.
Having 6 players in the group (including 2 leaders) will slow combat down considerably and he may have the feeling he needs to throw in extra stuff to challenge PCs.
KotS is a very good example of the frequent need to take published adventures as a starting place ti build upon. Personally I think all of the eastern part of lvl one should be totally cut, and its as simple as putting a wall where a passageway leads.
As for feeling like every time you succeed you are beset again ... well if that is a problem for you then you'd hate playing in one of my games!

I consider it my job to make my players feel constantly bruised, battered, beaten, hounded and suffering. Of course they have their victories and brief moments of rest. But many of them lead or even cause new challenges to arise.
[sblock=Example: Warning: Wordy and srtrays from the topic] My PCs have just removed a shard (remnant from the shattered body of the now deceased goddess of magic) from the head of the main NPC, who had been fighting against a monsterous creature that beset the town in a most diabolical way. The PCs had previously found several clues to suggest that it was that same NPC who was also responsable for having released the monster with an apparatus he invented capable of separating the soul. They also discovered that he had been planning to release someone from their prison who he calls 'The Father' with the same apparatus. When he was questioned on these matters, every time he tried to speak of certain things he would be stopped by a splitting pain in his head. When they discovered the shard was the cause, and having alterior motivations of their own to possess the shard themselves, the PCs took the main NPC to the town sanitarium where a delicate operation was performed by the physician to remove it.
They defeated the Creature after a battle of epic proportions waged literally across the entire town (that I made a scale battle map for on a massive sheet of tansparent plastic) as the moster used the NPC's aparatus to open the very gates of the shadowfell which has seen them finally reach paragon level.
And just as they have reached this pinnacle of victory after countless months of persecution across the face of the continent by secret socieites, vengeful drow, regional authorities and skilled assassins, dragging themselves through a deadly bog only to walk into a nearly fatal ambush by aforementioned assassins, to survive only to walk into a blood sacrifice ritual which they inadvertantly volunteered to participate in causing them to be wildly sidetrekked as they slip through reality into a haunted castle trapped in space and time doomed to play out the bloody massacre that repeats itself day after day. The curse finally broken, the return to their own time, but no rest for the wicked. On to face the resurgent horde that call themselves the Red Hand ... etc etc all in an effort to find the NPC with the shrad lodged in his head, the man who stood against this chaos, the chaos he himself had caused.
Little do my PCs know their victory once again is going to seem very hollow when they discover that it was the shard that inspired the NPC's goodness, and once removed his self knowledge will come floodingback ... and his design to release The Father, Father Chaos, will resume in earnest (hopefully with the PC's help). For little do they know the depths of evil to this man known as (and this is the beautiful thing about playing D&D with people who are absolute virgins to RPG because they had no idea who this NPC was even though they knew his real name) ... Strahd Von Zarovich!
Hehe, I think the last time my PCs were able to comfortably just relax, go shopping, enjoy a few weeks rest (err ... I mean a good nights rest) was at around level 5. It's been full on intense. I've loved it! By the sounds, you'd hate it! But that doesn't necesarily make a bad DM IMO.

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