As you seem pleased with the build quality of your Lanka, why not explore the whole Hymer range which would give you a very wide choice of layouts and engines. I am sure that you will already be aware that Neiman Bischoff, Hymer, Tec, Burstner, Dethleffs and a few others all come from the same family with quality build expected but with a variety of equipment levels and layouts to satisfy most needs.
I do not wish to put down any make of van but do agree with you that we in the UK who produce some well built vans, have sadly also produced many vans built down to a price with evident consequences.
I am aware that there is an attempt being made to improve the quality of materials in UK vans, to overcome a history of unforgivable damp problems, which I hope is not too late. I like many others lost confidence over recent years in UK vans, which is unfair I know, for having owned an Auto-Sleeper which was both seemingly well designed and built, I should know better.