Hard to improve on the Bertrand-8 design. Are you able to make the table wider? If you can open it up to 6 or 7 feet, then your options improve.
Otherwise, that's about as good as it gets unless you want to make a "plate of spaghetti" track and start adding all kinds of over/under track and multiple levels.

 

Thoughts? Suggestions?

First off it looks very nice! Your layout reminds of my second (even with it being twice as long) although it's much better done than mine. Obviously you know more what you are looking for than someone else however I'd lean towards two changes... making the turn at the end of the long straightway more sweeping (use the entire table's width), sacrifice most the shorter straight and replace it with various radius curves. Perhaps creating two overpasses or one longer one which should allow for some nice esses and or chicanes. That would increase your turns' variety and add some uniqueness to the various sectors.

 

I did not know that the space station had room for a slotcar track. I bet those magnets are helpful in no gravity settings ;-)
Joking aside, I think Mr Flippant's comment is something I was pondering myself: it seems that you have enough space to make the table wider.
I like the Bertrand fo8, but I find it boring after a while. Having 4 different "depths" (compared to only 2 with the fo8) I think it is more interesting.

 

For variety try reversing your over/underpass..I do like it as is..

 

the end closest to us could be made into a larger radius curve with various sections ie r1,r2,r3,r4,r4 or reverse order so as the right hand straight came along the right hand edge of the table ,that would add length but also give this end curve a bit of variety and speed with a challenge .that would be my first change , after that more width in table ,up to 2100mm wide ( 7ft ) would give you a heep more options

 

Yeah, that might be a good change. I think a little kick out and a wider radius is one of the other features of that layout I like.
I just adapted it to 5x18 with a wide open turn at that end.

 

Or even this, taken from Greg's previous post

 

In my opinion (biased and unrealistic - I am more determined than I should be to fit small interesting layouts into spaces using Carrera!) you should be able to get a reasonable amount of variety in a 5' width. Its about as narrow as you can work with in Carrera. I'll keep this in mind for the next few days as I saw something on social media recently that might fit, will see if it pops up again.

 

Haven’t found the one but here’s another idea

 

Ya cant beat a decent figure eight with a good chute,in my estimation. If you try too hard, layouts become a spaghetti bowl, as Greg mentioned.

 

wonder if @kalgani has any ideas? In the mean time another Bertrand variant with bigger loop, not unlike what has already been mentioned but thought I’d post it anyway. Don’t bother unless you already have the bits lying around as it’s a similar flavour of what you already have.

 

If that could be a banked turn, it would effectively lengthen the straight, but then you'd need to shift the pit lane further down until the track is flat again.

 

My current layout has a moderately banked R2 turn (180 degree turn) at about 7 degrees banking, as I didn’t want my lower cars bottoming out on a full R2 bank. I just propped it up, it allows faster corner speed and I just used flat track sections. Not an ideal engineering solution in theory but it worked for me, don’t really have any issues.

Also, have a look at post #61 on this page: Carrera track ideas

Apologies for lack of direct image and link formatting, I've clicked something bad and have lost the option to do both.

 

Some good ideas here. I am also wondering if I should try to add another lane changer (probably a double) to my current layout.

 

that is a good idea ,shift the single lane change you have at the end of the right hand straight and put it just before the pit lane ,so someone can change lanes and then enter the pit at the last moment if you are using fuel sometimes people forget and find themselves in the wrong lane ,then put in a double where you took out the single ,mainly for lane changing ,but if you were to make that bend a larger radius turn then the lane changer would defeat the purpose ,cos you would need to slow down for the lane change when more speed could have been used in the big bend,
so you need to think about what you intend to do for layout first as it sounds like you want to go bigger . get a layout you like to drive first and then when happy ,start putting in lane changes ,some people say lots ,but less sometimes make for more tactics ,

 

I put some more tracks on the table...
Fast opening corners, narrowing corners, slow tech parts and fast S.

Viewability should be ok, if you are standing 3ft away from the table.
The borders in the middle right are a bit tricky but with some 8mm wood
you can build there some induvidual borders for this part.

Softy Bahnplaner - DER Online Streckenplaner

Seit 2013 - Online die #1 - DER Streckenplaner

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Hope you will give it a try.

Edit:
it's ~21m / 68ft both lanes.

 

Another Idea:

Softy Bahnplaner - DER Online Streckenplaner

Seit 2013 - Online die #1 - DER Streckenplaner

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