(1) The water: in general, with extract brews, the rule is, don't mess with the water if it tastes alright. If it tastes like bats roost over the source at night, get a big container of the bottled stuff or use a charcoal filter. Chlorine is another matter. The filter will work, but you can also let the water stand for a day and then bring it to a boil for a minute or two before adding the ingredients. Unless your water has chloramine, rather than chlorine. In that case, use the filter or Campden tabs according to your LHBS's directions.
(2) The kit yeast may be older than me. Since it's summer, kveik might work out better. Lallemand provides these specifications: "LalBrew Voss™ supports a wide range of fermentation temperatures between 25-40°C (77-104°F) with a very high optimal range of 35-40°C (95-104°F)." If you can pitch in the high 20s or more, fermentation will raise the temp in your cupboard into the optimal range and finish fast. You will get some yeast flavours from kveik. Opinions on them differ,
(3) That looks like a low-flavour recipe. Calling a kit "cerveza" is a peeve of mine. Cerveza is Spanish for beer, not a style, and Mexicans brew a good variety. It's like packaging a kit for "Australian beer." But Morgans probably mean Corona, which is pretty bland. Hop flavour will be slight.
