Should I consider foster?

Currently I am a full time student (event though I'm 37), with some work from home income. I am comfortable though not wealthy financially and have long student holidays during which I am at home (I can't afford to go abroad) and am either working in my house or enjoying working with and training with my dogs.

I am in an almost perfect position to foster and have contacts with a number of rescue groups so I know there are loads of dogs out there who would love to have a break from kennels and time in a house, even if just for a holiday.

Pharaoh is getting older (12 pushing 13) and to be honest I probably wouldn't foster until he has gone to the bridge... unless just the right sort of dog came along...

Kismet is much better with other dogs now than she was, though she still wears her muzzle while out on walks, just in case. We have more positive than negative reactions to dogs these days and she can greet and even play with 80% of the dogs we meet on walks... I can usually spot the sort she doesn't like and keep her distracted and happy on a short leash until we are past and then we will maybe have one incident a month or so where some evil little monster just heads in and has a go, hence the muzzle still.

In the house she had a couple of fights with Selkie though one of those seemed to be an attempt to remove a cyst we hadn't noticed, the rest were probably just bitch to bitch related and were never reciprocated by Selkie so were never that bad, no damage to either side, with Pharaoh its the usual things that trigger spats between dogs that live together, a squabble over the ownership of a toy, or once Pharaoh fell off the bed onto her and the pair of them woke up thinking the other one had attacked them...

The spats between them are very rare and easily broken up, with little harm done, though Pharaoh always ends up with a couple of holes cos his skin is made of tissue paper, we just wash them out, keep an eye on them and all is well in a week. The fights never last and the dogs will be curled up on the sofa together minutes after!

In the past we have had Ayla the malamute come to stay and her and Kismet got along famously, although needed to be separated to sleep or they would play all night and my friends collie cross and akita cross have come in and been tolerated fine by Kismet. NO spats or issues, she seemed to love their company and played happily with them while they were here...

BUT

Kismet is 3yrs old Husky mix with known occasional dog aggression issues.

She is stroppy, bossy and can be temperamental and possessive.

It would probably not be safe to foster a small or 'delicate' dog as what is just a spat between her and pharaoh could be fatal to a chihuahua!

1. Do you think a rescue would, or should, consider me for a foster?

2. Do you think it would be fair on Kismet or on the foster if they did have a fight while they were here?

3. Is it irresponsible of me to even consider another dog when I know Kismet can be stroppy and could get aggressive? I muzzle her on walks because I don't 100% trust her with other dogs, but I would not muzzle her in the house.