I have not worked with Merchant that much so not sure how much help I can be. I did check your site and it seems to be a bit sluggish here in the states in KCMO and I am on DSL. Did look like you used some pretty big graphics. It was ofcourse hard for me to navigate since it was no in english so was not always sure if I was looking at a graphic or text. The site you mentioned dragonestore I did a check on and they are not with WestHost but anouther hosting company wich could be part of it. I have heard others complain at WestHost that Merchant is slow but ussally it is with the admin interface.
I don't think it would hurt to get rid of the extra moduals that you are not using. I visited the Miva Merchant site (seems a bit slow itself) and looked for info on Modules. This I did find a page http://www.miva.com/docs/api/
that has a list of pdf docs you can look at. Note
The docs for Merchant 2 wich I think is the version WestHost runs is at the bottom of the page. They are up to version 4+ now. The dragonestore site looked like it was running version 4. In looking at the pdf file it looks like there is a function to uninstall a module. Like I said I have never seen the current admin interface so not sure where to tell you to look for it. Guess I need to install Merchant on one of my accounts so I can at least refrence it.
To recap my thoughts on this:
Check to make sure your graphics are optimized and small.
Remove any modules you are not using.
Perhaps look into upgrading to version 4+. (not sure if that would really help)
Keep speaking with WestHost to let them know that you are not satisfied with the speed of Merchant and see if they well do anything to help. Sometimes you have to keep asking different levels of tech before you get to one that can help.
If you can not get Merchant running to a speed you are satisfied with you may have to switch to a different hosting company. I do think that if you keep on WestHost that it could improve if you can hold out. I think they are still so focused on the remaining upgrades that they are not doing much on updateing existing problems that are at least running. I know they keep trying some things here and there but do not think there full attention is on it right now. They did put out the questinair on thier service and how to improve it so they me be ready to move to solveing some of them. The more you can learn about Merchant the better off you well be. I have been working with the program that runs this forum the basic that WestHost supplies is just that when I dig deeper and look at others who use it and visit forums on the program I learn all kinds of stuff that is of help.
I wish I could have given you a clearer easiier answer. I well continue to look around and see what I can find out about speeding up Miva Merchant and if I find anwers I well post them in this thread.