Clint23Shannon
It is true that the 5 Ghz band has the capacity to be faster than 2.4 it is also true that it doesn't have the penetration.
The HT2000w Modem/wireless router is a new piece of equipment and as such can be expected to have a few bugs that need to get ironed out.
Not all of the wireless radios in Routers are created equal. They all have different "radiation patterns". Some are best suited to multi-story homes, others for long ranch style and so on. Router placement is very important ... central elevated locations are usually preferred. Adjustment of antennas is needed at times. Because the "radios" are internal to the HT2000w it can be difficult to elevate the Modem and the antennas are internal so they can't be tweeked in the normal sense.
There is no magical differance between Gen4 and Gen5 other than the greater capacity and speeds that Echostar19 offers. The only differance is that you chose to use the HT2000w's internal wireless radio rather than your own router.
I would suggest that you disable the wireless portion of the HT2000w and connect you old router. The IP addresses of the HT1100 you had with Gen4 and the IP of the new HT2000w are the same so no configuration changes need to be made.
Here is a link that will allow you to download the HT2000w User Guide and the more detailed Installation Guide:
http://customer.kb.hughesnet.com/Pages/1073.aspx
They will be the top two items on the list.
The install guide will provide you with detailed info on disabling the HT2000w radios.
IMHO the wireless portion of the HT2000w is not yet ready for prime-time ... so don't use it.
There is no way I would give up the functions and features of my Asus RT-AC3100.
Why stress? You were fine for 2 years with being double NAT'ed, you will be fine again using your own router.