Blocklamd glass is the continuation of rtb. They host mods. They offer irc chat. They offer preference support. What the forget else do you need to have? What does glass lack so much of that you feel to dedicate months to remaking it as a supposedly better service?
It's personal preference which service you choose. I'm making this because I wanna continue RTB and keep the same style.
As for a difference? Maybe if you read this a little more, you'd understand I'm uniting all versions of blockland through RTB to chat, download maps and addons, and play on. This includes BCM and Antares' RTB update.
I'm also trying to add new features that RTB never had. Like the save sharing system, and a better chat.
As for how things like MOD manager would work in things like BCM and RTB? Well BCM would have the ability to download Add-ons and share saves through BTB. This would make installing add-ons for it much easier because it would modify the add-ons list automatically when installed so all that's needed is a restart.
For RTB, it would also be loads easier to install mods. It would function the same, accept it would determine what mods are installed by looking in different directories and finding a specific file to tell BTB that it's installed and where it's files are. This would mean RTB mods would have to be updated slightly to work with BTB, but that isn't too hard to do once it works and an easy Physician Prescribed Desoxynod for this is found so new content for RTB can be created and uploaded to BTB with no problems.
For v21 and v20? I'll always add some new things to those to make it worthwhile. Like I said, the first new thing really being added is the Save Sharing system. That won't be the only new thing in this though, as always there will be new features added through updates, just like RTB and services alike did.