multi-form wereform

[JDK002]

So I've been kicking around this character idea for a little bit and wouldn't mind some advice on making sure it's balanced.  I'm trying to make a were-spider character.  But the idea of someone turning into one single spider seems a bit underwhelming.  I have two ideas that I would really like to use together for one character, just not sure how I should set up the powers and refresh costs.

My first idea was the character turns into a swarm of spiders roughly equal to his body mass.  Each one containing a fraction of his consciousness, meaning the spiders have to stay within a general radius of each other or the stray ones turn into ectoplasm.  This counters any "i know everything that's going on because I have spiders at every location we've ever been do this scenario" game breakers.

The second is one large spider with the same body mass as the character in human form.  I figure a slightly modified Hulking Size power would work (it's big for a spider).  But trade out the stealth penalty for something else, as a 200 pound spider that can climb walls could still be stealthy.

Both ideas alone are easy enough to do.  But if I want a character that can do both, would just making them double up on Beast Change be fair?  I'm just not sure -1 refresh balances out a 3rd stat load out you can flip to pretty much on the fly.  Though I'm thinking powers taken for each form would never overlap.  By that I mean if the giant spider form had Claws and Venom, the spider swarm would not.

[Becq]

I'm fairly sure that Sanctaphrax had a Swarm power and a Dual Form power somewhere in his custom power thread.  I think the Dual Form power may have been a limited version of Modular Abilities (ie, you get two specific power layouts at a reduced overhead cost of -1).

Something to consider, though, is that for a human to be able to change into a single fixed alternate form is considered fairly traumatic per the flavor text.  Turning into a horde of spiderlings seems likely to lead to something along the lines of

the stress and strain placed on the sense of self inevitably leads to a psychotic break of some sort

.  Which could in inself make for an interesting (though at best eccentric and more likely flat-out insane) character.

[Sanctaphrax]

SWARM BODY [-3]
Description: Your body is made from a multitude of lesser creatures, making you more difficult to harm.
Note: This power often has a drastic effect on the range of physical consequences that its user can take, and many characters with it will be unable to use conventional weapons and armour. This is not part of the Power's effects, and should be treated as a Compel if it ever impedes a character. This power is usually, but not always, taken with the Amorphous Form Power.
Skills Affected: Endurance, other physical skills.
Effects:
Chipping Away. Single-target attacks don't hurt you much, no matter how deadly they are. Whenever you would suffer physical stress from an attack that does not encompass your entire body, you take only a single point of stress.

QUASI-MODULAR ABILITIES [-Varies]
Description: You have the ability to alternate between multiple powersets.
Musts: You must "pre-pay" a number of refresh points equal to the total value of each set of powers that this power affects, plus a surcharge of one refresh.
Skills Affected: Varies.
Effects:
Two Powersets. Pick out two sets of powers, each with a total refresh cost one less than the cost of this power. You may use either set of powers, although it takes a full action to go from using one to using the other. The GM decides what is and what isn't a valid choice for inclusion in the powersets provided by this power.
Item Of Power Collection [-0] You own multiple items of power. Design a number of Items Of Power equal to your Resources skill. At any given time, you may use or loan out items with a total refresh cost up to one less than the refresh cost of this power. You do not receive the Item Of Power discount. If you have the Tracing power, then you may summon and dismiss these Items Of Power out of and into thin air. If not, you must treat them as physical objects.

[JDK002]

Awesome, exactly what I was looking for.  Skimmed over the powers thread but couldn't find them.  You are a super hero.  Thanks a ton.