Star, you already have a great portrait lens in your collection, namely the Tamron 90mm Macro.
But if you want a very fast prime, then the 77mm Limited, Sigma 85mm F1.4 or DA*55mm. Also the Manual 55mm F1.8 in various guises is a cracker!
For zooms, the default choice for me is the DA*50-135mm - an Outstanding lens for studio work.
For full length shots, The DA35mm F2.4 is a little gem, and cheap too.

Hope this helps

Personally I would either go with your 16-45 and Bigma, but if your heart is set on a more flexible zoom for most uses, I would suggest the 17-70 that has already been said.
I would also say (if you already have one) a fast fifty too, either the FA 1.4, 1.7 or the new 1.8 model. Why? you may find there will be time that you want to take shots with shallow DOF, plus they are small and light so won't take too much of your hand luggage.

One word - WOW!

Looks like the s model is to be bought.........

Why did I go Pentax? Okay, here we go.
I had (still have) a Praktica SLR. I went to Peru and got great shots. However I found it a bind to MF, certainly when shooting the condors. When I got back home, I decided to invest in an AF SLR with metering etc. I went to City Camera in Croydon (before they were bought by Jessops) and got some good honest advice about a replacement camera that gave me the same control as my Praktica, but in an electronic body. The Camera? the Pentax MZ-5n!
The CaNikons at the time did not give me what I wanted.
A small lens collection came along, and then Digital. Initally I was not impressed, and stuck to film. However, Digital took hold (I got a Fuji S5000) and then I was impressed. So, due to my lens collection, which included a not cheap Tokina 20-35 F2.8, I decided to take the plunge and buy myself a DSLR. The result was the *istDS. I have not looked back.
Frustrated at times with lack of certain focal lengths, but now VERY happy with the current holy grail of Pentax DSLR's, the K-5! Oh I also have a rather nice range of lenses too. Roll on the Big lenses and FF from Pentax now.

Cottonbuds. Always have cottonbuds in your bag. They work perfectly to clean the contacts. I always have some with me.

Nice little tip from Offertonhatter....



Sorry, that sounded like gloating, its not, just a good tip (sic)

Praising Mathers? That was probably me. I got my K-5 from them and my Pano LX-5. Great shop to deal with and have good deals too

Bowens do a full kit (2 heads brollies and/or diffuser, plus wireless triggers) in your price range. Although I don't have Bowens, I have used them numerous times and work well.
Mine? I have Interfit EXD200's, which for a budget range, work very well.

I saw this too, on B&H, so did a check. With shipping and taxes (they add them at the end) it still works out £80 less than over here.
Not that I have got one mind, but it IS tempting....

Probably my DA*50-135mm. Hardly off the camera, and used for events, portraits, outdoor, monsoons etc etc.

Bargain lens - my K-55mm F1.8 £20 on e-bay a few years back.......

I have done a number of events and normally I set the camera to ISO200 or ISO400 and leave the camera in Program. Most of the time it works a treat. Sometimes (the P-TTL being what it is) some shots are underexposed, but the K-5 being what it is, you can pull back the images in RAW without any issue.

Hope this helps.