Flamers should get some kind of benny when dealing with units under cover. Anyone whom says otherwise I would suggest they talk to old Marines whom used them in 'Nam, or better still against the Japanese when they were holed up in armoured pillboxes. Flamers should also call for a Ld roll of some sort for the unit being targeted with them, as fear of fire is instinctive for any living thing. Yeah, yeah, I know, I'm applying RL for a game, but I remember using them in my old Squad Leader games, and those checks were made. On the downside, flametroopers in RL had a short life expectancy as they were first priority to be sniped off. On the plus side, I like the thought that all weapons are going to have a use in the game again, as now there'll be a reason to equip units with things other than just a few choices.
Hope: We get our own Codex all to ourselves as is right and proper, with all our actual characters back in it (including real rules for Ephrael Stern)
Wishes: Give us Repressors, and actual choices to fill out all of the slots in our army.
Fears: The usual: we'll either get nerfed or squatted. Although the fact we got something printed (not some online thingy, but actual dead-tree-and-ink) for Imperial Agents and the Shadow War Armageddon tells me the latter won't happen. GW seems to be listening to their old customers.