i dont think it needs to be that radical..
.there is planty of room on the freight avoiding lines for extra platforms and a tunnel exists to bring waterloo nad guildford trains into this area thus eliminating the junction to the east of the Station.
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Platform 4/5 can then be used for west of england services...8/9 for bristol/south wales services and the new platforms for stopping services....strageic provision of freight lines can be incorporated too.(reinstate the line between 8/9 and make it revesible)....oh, and a Gricers Buffet at a conveniant spot would be brilliant....
finally...is Reading West closed!!! shock horoor.....didnt know that