Hi,
I come from Fuji background. I will address your issues.
1. If you need the zoom range that you achieve with your Fujis - please don't buy a DSLR. They are incomparable. Fuji SX1 is a very able camera but you must be registered to a Fuji X forum to know the problems associated with a big long zoom lens. The zoom lens is wobbly and there are many sensors which have a white blob on it. (Canon SX50 gives 1200mm zoom with a 450$+ or - range).
2. Fujis suffer from extreme barrel distortion. All of them. (At wide end). People claim that they can be fixed using PP, however fixing a barrel distortion which almost brings the building on the side of the picture to the center of the image is almost destruction. I can share sample. Infact every camera almost suffers from distortion - However Pentax has In-camera removal.
3. Fuji HS30 is a very able camera. Comparing XS1 and HS30. XS1 wins by a huge margin. But if you see close enough HS30 and XS1 BOTH are not the flagship models. Think deep and you will know why. It is because they don't have what it takes be the flagship. XS1 was launched with a big bang but it was muffled so fast - No one got to know. Fuji X100 X10 X100s get to be the flagship models.
4. About ZOOM: If you need very high zoom, you can go for bridge cameras, No problem at all. However you will never achieve the picture quality - Specially sharpness.
5. Bridge sensor and DSLR sensor has been explained above. Bigger the sensor the better - Everyone knows it. You can do research why on your own. I am sure you know. (However XS1 has 2/3" sensor - It is one fine piece of equipment with it's own problems).
6. I used to think like you before - Oh big zoom - Great! At 500$ price this is a steal. Later I realized those are just gimmicks. You almost never need that kind of zoom, unless you are into car racing / bird photography.
7. Distortion of K-5 and K-5 II is same and they aren't so much camera dependent as they are lens dependent. Again, in camera fix. Plus PP fixes rest - As Adobe has almost all lens and Pentax models.
8. K-5 is steal of a deal with its price. however I would still pickup a K-5 II (Already an owner). Very able - fast - spot on camera.
9. K-5 II sensor is a newer sensor (Atleast claimed) How new it is I am not sure - However it can perform an Auto focus in darkness much faster. Also it's AF in general is spot on and faster.
10. Pentax lenses are backward compatible to my fathers day of taking pictures. You can buy inexpensive manual lenses with amazing glass for even 10 - 20 to 30$s. (Having said that DPREVIEW has a thread running currently about their lenses VERY HOT! Here is the link
Pentax lens prices.: Pentax SLR Talk Forum: Digital Photography Review you will see that current Pentax lenses are freaking expensive - I guess poor management / marketing decision).
I know of a professional photographer (Personally) who is from Montana who uses HS30 and is a professional photographer (Sports / NASCAR). He even sells his pictures. People buy. I am not saying bridge is a wrong decision. I am just saying you have to know what kind of photography you like and then choose your equipment (Features which are kind of GOOD-TO-HAVE which you will NEVER-USE) can be avoided.
The only camera which currently sees Pentax K-5 II eye to eye would be Nikon D5100 (Beginnner / Enthusiast) or Nikon D7100 (Enthusiast / Semi-professional). Considering you already bought lenses for K-5 I would not go in that direction.
The reason why I bought Pentax K-5II - Firstly I love landscape and it fit the purpose with "highest" APSC dynamic range sensor and great color depth for my occasional portraits secondly it was not so expensive when I bought it third and last it was a complete PACKAGE of a DSLR which I wanted to buy (Weather-sealing, Magnesium alloy body - I dropped my camera already once, PENTA - "PRISM" OVF, Fast AF, 7 FPS - I could NOT have asked for more.)
HTH - Cheers!