[rabbit73]

If there is no elegant or effective "integrated" antenna to help me

or could I use an antenna than can do H-VHF well and UHF

There are antennas that combine VHF-High and UHF like the Winegard HD7694P, 7697, and 7698 series. They try to match the VHF and UHF gain of each member of the series, but since 8 and 10 are much stronger than 25, you need more help with CBS on 25 because of the impediments of an attic location, other buildings, and hills.

The 7694 has about the same gain as a DB4e with a CS 5, but the UHF section of the 7694 is a yagi and we have found that a bowtie antenna like the DB4e performs better than a yagi in an attic.

1. (a). DB4e + VHF dipole
2. DB8 + VHF dipole
3. DB8 + ClearStream 5

1. is the lowest cost of the three and favors UHF because 25 is weaker
2. a little more gain for 25
3. more gain for 25 and more for 8 and 10

(b). ClearStream 2V (CS2 + the VHF dipole integrated)
(c). Winegard FreeVision FV-30BB
(d). Xtreme Signal HDB8X-NI 8-Bay or the 4-Bay version + either VHF dipole or the Stellar Labs VHF 30-2475 suggested by MikeBear?

b. C2V not quite enough gain for 25. OK for 8 and 10
c. very inadequate for 25, probably OK for 8 and 10
d. that would work, and keep the cost low, but I don't have any personal experience with them

1. Is it best to locate the splitter near the antenna (south of the UVSJ) and take two long cables to the respective TVs (50' and 60') approx? Or, put the splitter near the 1st TV (upstairs BR) - about 50' from the antenna and drive the other cable 15' straight below?

The signal loss is about the same for either approach. I favor plan B because it uses less coax and it would be easier to add a preamp near the antenna if necessary with only one downlead.

2.If I do use the FM filter, where should I place it? After UVSJ?

      DB4e >
            \
            UVSJ > FM filter > coax > splitter > TVs
            /
VHF dipole >

The AD VHF dipole kit contains an integrated UVSJ; 
other brands would require a separate UVSJ

If you need more signal for splitting, replace the splitter with a Channel Master 3412 distribution amplifier which combines an amp and splitter in one unit:

UHF antenna >
             \
             UVSJ > FM filter > coax > CM 3412 > TVs
             /
VHF antenna >

If you need even more gain because the signal losses are more than average, use a preamp at the antenna, with its power inserter and a splitter down below:

UHF antenna >
             \
             UVSJ > CM 7778 > coax > power > splitter > TVs
             /                       inserter
VHF antenna >

The 7778 contains an FM filter that should be ON. If it is not sufficient,
add an external FM filter before the preamp input.

What I have told you is just my opinion based on my experience; I can't give you a guarantee because there are so many variables. If I were there with you I would be able to make some measurements with my signal level meter (SLM). Hopefully, your TV has a signal strength indicator to help you. You need to take ADTech's reference about Forrest Gump seriously that you don't know until you try it.
http://www.wavsource.com/movies/forrest_gump.htm

Tom Hanks: "My momma always said life was like a box of chocolates – you never know what you're gonna get."